Fixes #23705 - Do not associate ptable snippets

Fixes #23852 - Properly escape html in template preview errors

Fixes #23386 - Exit fullscreen when pressing ESC

Pressing the escape key should make the editor exit
the fullscreen mode. Nonetheless, when this key is pressed
the "exit_fullscreen_editor" function is called but
it was renamed to "exitFullscreen" which ends up with an error...

Fixes #21624 - eslint update to airbnb-base

Replace existing custom rules with airbnb-base config.
Eventually we'll want to to move to the full airbnb config
with react and a11y.

http://projects.theforeman.org/issues/21624

Fixes #21112 - Only initialize host preview once

Instead of adding the event every time the form is loaded, only do it
once when the editor is initialized.

Fixes #21454 - fix editor fullscreen mode

Fixes #20900 - Combine Template editor and template field

Fixes #20240 - fix fullscreen mode in ace editor

Fixes #20573 - Include searchbox extension

fixes #12419 - template preview host has typeahead

fixes #16288 - moves ace editor to webpack.

I've tried to limit changes to minimum, besides fixing lint errors i've:
- moved to brace package (as its compatable with br and webpack).
- added ERB as a syntex highlight.