remove editor preview css styles from mobile
move editor spinner css to shared (base) css
width 100% for editor on mobile; no preview

also  remove box-sizing mixin, use native CSS3
min-width of 1280px for editor on mobile??

OH HELLllll TO THE NO
minor mobile editor tweaks
few more mobile editor tweaks
oops
add better mobile inline title edit styles
hacky override of inline select2 width in editor
Fix buggy autocomplete behaviour for non-US keyboards

This change moves the code for actually entering data from the keydown handler to the
keypress handler, which can reliably catch the character entered (rather than
the key pressed).

This is my second attempt at
https://meta.discourse.org/t/typing-shows-on-non-us-keyboard-layouts/20449
without doing dangerous refactoring.

This does not fix the issue reported in
https://meta.discourse.org/t/overly-aggresive-emoji-autocomplete/20691/7
as that is a different bug.