New Bottom Help text

Summary:
Changes to the text in the bottom help text include:

- Add missing text: Mouse actions have been missing and have therefore been added
- Improve code: Most of the texts have been similar, redundancies have been mostly removed
- Make texts more clear: Especially the shift option has been added to the other texts to make clear that this is an additional feature, which can be used in these modes
- Fix translation issues: texts have been seperated before for visual reasons, which makes translation hard. Splitting the text up should be done automatically (row wrap) or by the translator (add \n) ... for now the bottom help text is just wider, layout will be fixed in my other revision
- Make model easier: Only one text each actions, code for layout is easier (see my other revision)
- Updated texts for special modes: Some commands where not possible when "capture is enabled", others have been missing

Further ideas:

Mouse/keyboard actions should be the same e.g. shift should active fine-tune with mouse and alt should active magnifier with keyboard. This would allow to write a more compact help text.

Use icons instead of words (e.g. icons for right-click/left-click, alt, strg etc.): Icons would save space and are easier to read/use

Test Plan:
Check if texts are correct (grammatically) and usefull. Check if there is any text missing for the different options. Suggestions for better texts, changes are very welcome

{F7318202}

Reviewers: #spectacle, #vdg, ngraham, davidre

Reviewed By: #spectacle, #vdg, ngraham

Subscribers: The-Feren-OS-Dev, ndavis

Tags: #spectacle

Differential Revision: https://phabricator.kde.org/D23687