Replaced images with vector drawables

[BlackyHawky]

Fixes #195

Almost all the images included in the drawable- folders have been replaced by vector drawables.
Moreover, Material style icons now use the Material design.

The following images are concerned:

Expand to see images concerned

Images concerned	Images concerned
ic_ime_switcher_dark	sym_keyboard_search_holo_dark
ic_menu_add	sym_keyboard_settings_holo_dark
ic_notify_dictionnary (deleted as no longer in use)	sym_keyboard_shift_holo_dark
sym_keyboard_clear_clipboard_holo_dark	sym_keyboard_shift_locked_holo_dark
sym_keyboard_clear_clipboard_lxx_dark	sym_keyboard_smiley_holo_dark
sym_keyboard_clear_clipboard_lxx_light	sym_keyboard_space_holo_dark
sym_keyboard_clipboard_holo_dark	sym_keyboard_space_lxx_dark
sym_keyboard_clipboard_lxx_dark	sym_keyboard_space_lxx_light
sym_keyboard_clipboard_lxx_light	sym_keyboard_tab_holo_dark
sym_keyboard_delete_holo_dark	sym_keyboard_voice_holo_dark
sym_keyboard_incognito_dark	sym_keyboard_voice_off_holo_dark
sym_keyboard_incognito_light	sym_keyboard_zwj_holo_dark
sym_keyboard_incognito_lxx_dark	sym_keyboard_zwj_lxx_dark
sym_keyboard_incognito_lxx_light	sym_keyboard_zwj_lxx_light
sym_keyboard_language_switch_dark	sym_keyboard_zwnj_holo_dark
sym_keyboard_numpad_key_holo_dark	sym_keyboard_zwnj_lxx_dark
sym_keyboard_numpad_key_lxx_light	sym_keyboard_zwnj_lxx_light
sym_keyboard_return_holo_dark

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In android studio, some images look a little imperfect (because I created them myself from PNG files), but it's impossible to distinguish these imperfections on a tablet or phone (see screenshots below).

Expand to see affected images

• sym_keyboard_numpad_key_holo
• sym_keyboard_numpad_key_lxx
• sym_keyboard_return_holo
• sym_keyboard_smiley_holo
• sym_keyboard_tab_holo
• sym_keyboard_zwnj_holo
• sym_keyboard_zwj_holo
• sym_keyboard_zwj_lxx

---

Expand to see screenshots after modifications

Before	After

Tested on Huawei phone with Android 10 and Samsung tablet with Android 13.

[BlackyHawky]

The 2 "force-pushed" correspond to :

1. Material style icons now use material design;
2. The "+" sign in the language settings now uses design material too (I had forgotten to include it in the first "force-pushed".

[Helium314]

To be honest I don't like the new icons, and would like to keep the old ones.

Best would be to add a new style (in addition to the current holo & material) with these icons. You could also use this new style to add the more rounded key style from #16. (same goes for the changes emoji icons)

Ideally this would be done in a separate PR for better separation of changes.

Btw could you add the license for the new icons? I'm planning to add SPDX license identifiers wherever possible (mostly this will change the long license headers to one or 2 lines, also clarifying that GPL 3.0 is used too)

[BlackyHawky]

To be honest I don't like the new icons, and would like to keep the old ones.

Don't worry, as I said here #195 (comment) these changes were simply a proposal, with no certainty that they would be approved.

Ideally this would be done in a separate PR for better separation of changes.

Btw could you add the license for the new icons? I'm planning to add SPDX license identifiers wherever possible (mostly this will change the long license headers to one or 2 lines, also clarifying that GPL 3.0 is used too)

Of course. I prefer to close this PR and I'll do another one more proper.

[Helium314]

Alright, just one more thing: before you add another style, could you wait a little?
I'm considering to remove the border / no-border themes, and instead just make the keys transparent when key borders are switched off.
Since the changes will interfere with a new style, it would be good to wait until I either do the changes or decide to just leave things as they are.

[Helium314]

Oh, I just noticed updating the license headers created some merge conflicts... sorry for that.

I removed the holo no border theme, changing key transparency plus some workaround for the spacebar is sufficient. The material theme is a bit more complicated and thus the division into base and border will remain.

[BlackyHawky]

Oh, I just noticed updating the license headers created some merge conflicts... sorry for that.

I removed the holo no border theme, changing key transparency plus some workaround for the spacebar is sufficient. The material theme is a bit more complicated and thus the division into base and border will remain.

Don't worry; this PR is too messy anyway.

[Helium314]

Alright.
So I will not touch the drawables now, so there won't be merge issues for the next PR.
And if you want to add the additional theme, just tell me and I will not touch theme-related stuff until you're done.

Btw now with the new color settings it should be very easy to expose all colors to the user, as you had wished, while still defaulting to automatic color selection. You can do a PR, or I might do it at some later point.

[BlackyHawky]

So I will not touch the drawables now, so there won't be merge issues for the next PR.

I'll do it because I don't like not finishing what I've started 😅

And if you want to add the additional theme, just tell me and I will not touch theme-related stuff until you're done.

Btw now with the new color settings it should be very easy to expose all colors to the user, as you had wished, while still defaulting to automatic color selection. You can do a PR, or I might do it at some later point.

Great. I'll take a look and keep you informed. 👍

[BlackyHawky]

Best would be to add a new style (in addition to the current holo & material) with these icons. You could also use this new style to add the more rounded key style from #16. (same goes for the changes emoji icons)

Ideally this would be done in a separate PR for better separation of changes.

@Helium314: I'll keep you informed as promised:
I've almost finished the new style; I just need to refine the display of the hint letters. (As it is, they're good but I want to try something else in the code).

Finally, I need to separate the use of the new icons because I forgot you'd rather have 2 separate PR 😅

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Screenshots of current state : (space bar icon in Numpad view will be replaced)

Keyboard view	Numpad view

[Helium314]

Finally, I need to separate the use of the new icons because I forgot you'd rather have 2 separate PR

The new icons and rounded keys both belong to the same style, right? So I think it's very much ok to have them in the same PR.