remove codemirror
introduce ace + new template UI
Merge branch 'master' into from-cm-to-ace
Merge branch 'master' into from-cm-to-ace
templates: remove legacy code
templates: cache templates in browser
fix new-template issue
add marker to unsaved templates
refactor: move activation into template obj
templates: add save indicator
templates: blur save button after completion
templates: bold names
templates: bigger unsaved indicator
add fullscreen-button
refactor ajax: extract file controller
remove unused validate-file ajax action
fix PHP notice
enable some WordPress template tags

List of enabled tags:

- is_archive
- is_post_type_archive
- is_attachment
- is_tax
- is_date
- is_day
- is_feed
- is_comment_feed
- is_front_page
- is_home
- is_month
- is_page
- is_paged
- is_preview
- is_search
- is_single
- is_singular
- is_time
- is_year
- is_404
- is_main_query

issue #577