Failure of loading drawings will now close the drawing view and show an
error message, hinting at file or permission issues, instead of leaving
the user facing a continuosly loading interface.
Adds test to cover.
This also updates errors from our HTTP service to be wrapped in a custom
error type for better identification and so the error is an actual
javascript error. Should be object compatible.
Related to #3955.
- Updated comment routes to be simpler.
- Updated comments JS to align better with updated component system.
- Documented available global JS functions/services.
- Removed redundant controller method.
- Added window.$events helpers for validation messages and
success/error.
- Updated JS events system to not be class based for simplicity.
- Added window.trans_plural method to handle pluralisation/replacements
where you already have the translation string itself.
Fixes#1836
