Mock up add/remove tag UI.
working on normalization
Normalize method seems to work pretty well now.
Collections are now automatically normalized on both read and write.  Tests updated.
Work in progress
Fixing things up
Prevent table headings from scrolling out of view on collections index
table.

closes #2180
Move HeaderRowFixer out to application.js and application.css.scss

refs #2180
Output a blank line between pipeline status updates. closes #2182
Say when re-using existing jobs, even without debug mode. closes #2183
Hide top nav notifications and links to tokens/keys pages until user
is active.

closes #2188
Return only true or false for is_invited, never group uuid.
Fix crash if @notifications is nil.
Fix symbol key used in serialized attribute. closes #2186
Merge branch 'master' into 2179-demo-feedback
Render collection provenance graph top-down like other graphs.

closes #2184
Merge branch '2179-demo-feedback'

refs #2179
Merge branch 'master' into 2060-edit-tags-in-workbench

Conflicts:
	apps/workbench/app/assets/javascripts/application.js
	apps/workbench/app/assets/stylesheets/application.css.scss
Fix up tag and "add tag" button display.
Add and remove collection tags with ajax.