bump version to 1.2.0

[atticus-sullivan]

Adjusting the dates and version identifiers so we can release a new version (and upload to ctan).

@sgoudham you should be able to upload to ctan as well, do we want to try it this time? (else I can also do the upload, but I'll be unavailable for the next weak).

Other packages providing themes for latex beamer (like 1 or 2 (random selection)) have the topic/tag Presentation. Maybe we want this also set that one (just a field in the upload form).

Also should we document somewhere what to do in case of a new release (or so these version bump commits suffice as some sort of documentation)? So far it should be

1. adjust the version tag in the latex.tera and beamercolorthemecatppuccin.dtx files
2. add the changelog entry also in those two files (I'd say we just skip the entry if for the specific package/file nothing was changed now that we have two packages/files)
3. run make whiskers

[sgoudham]

I can try to upload it, yeah.

Maybe a nitpick but make whiskers should be ran before tagging/releasing to make sure the templates are up to date. Although, the main branch should always be in a state where the whiskers check is passing so no need to run whiskers at all. Just realised you meant for the PR, sounds good 👍

Also should we document somewhere what to do in case of a new release (or so these version bump commits suffice as some sort of documentation)? So far it should be

Yeah, a release section with some loose steps in the README would be appreciated. Even if it's simple / somewhat obvious to yourself.

[atticus-sullivan]

Yeah, a release section with some loose steps in the README would be appreciated. Even if it's simple / somewhat obvious to yourself.

I'd add it to this PR (making it a bit dirty, but it somehow fits).

[atticus-sullivan]

For the additional tag I think there is no field in the form, but there is always the free field for notes to the CTAN maintainers. We can suggest adding the Presentation topic/tag there.