Update phrase autocomplete sources [skip ci]
Refactor e2e tests to work with new browser/server split
Move code mirror themes to the components section

Due to the way we're applying the theme, we need to do some extra
finagling to the themes themselves to get them to work properly. That
finagling gets overwritten when we update CodeMirror, so we should just
keep a copy of the themes ourselves that don't get overwritten.

Alternatively, we should stop finagling things, but eh we're lazy!
Convert weird copy style directive to es6
Remove redundant mdn-like theme (see f7301dd)
Convert editor settings directive to es6
Refactor to controller as syntax in editor-settings directive
Listen for code mirror redraws via $on
Ignore old es5 files
Add .hd- prefixed versions of dark themes
Add neo theme to choices