Entry templates

[kurukimi]

Possibility to create entry templates and copy them into workdays.

Todo:

• Add delete template button for mobile
• Make sure entry keys and template keys cannot clash in entryContextProvider
• Refactor forms (entryForm, templateForm) and related similar (e.g, accordion rows) components into reusable ones.
• Consider if storing template entries in user-settings table single cell as json is legit or else create new table for template entries
• Validation for old entries, e.g, what happens when issue in template is no longer in the issue list.
• Add edit template button
• Button/tab for hiding template accordion?
• Allow partial templates: remove validation in template form and allow only "edit & paste" when pasting a partial template to workdays
• e2e-tests maybe in a later pr

Also, should maybe be split into somehow reasonable pull requests,