* Text editor word wrap, line numbers & syntax toggles now use consistent icons
that don’t change when you enable or disable them.
* Replaced icon toggle buttons in the snapping popover with normal checkboxes
and descriptive text labels. This makes it clearer which item is the main
radio button, is more consistent with other popovers, and allows us to use
more descriptive text.
* Added correct icons for grease pencil add menu.
* Added bespoke icons for grease pencil modifiers.
* Added icon for particle instance modifier.
* Added icon for fake user on & off states.
* Added correct icons for enabling/disabling modifiers in the dopesheet &
f-curve editor.
* Made it so the restrict viewport & restrict render toggles for modifier
update correctly when enabled or disabled, by flipping the order in the
icon sheet. This also required changing the outliner to match.
* Removed the few old remaining icons in the old style and made sure to replace
the last places where they were used.
* Updated many icons to be clearer & more consistent.
As decided in D910, we use a new icon for incremental grid snapping and use its old one for absolute grid snapping.
This also touches the library_data_broken icon .dat files, seems some changes on its .svg entry landed in upstream without updating the other icon files (already noticed this when committing icon for auto-offset, but removed it from commit - leaving it in now to avoid further confusion)
Icon by @plyczkowski (made a tiny edit as it looked a bit blurry in 16x16). Thx!
