Don't init select2/wysiwyg widgets outside of el

This wasn't done previously because I didn't know how.
Init invisible widgets as well.

To prevent initialization use class no-widget-init on the element itself or any parent element.

Fixes #1210.
Raw HTML textarea shouldn't be wysiwyg'd

Fixes #1211.
Merge pull request #1243 from mbertheau/fix-widget-initialization

Fix JS widget initialization