Proper display of non-question Embeddables

[#48685567] This is the background and showing/hiding of headings for XHTML embeddables.
Change embeddable "Name" to "Heading"

[#48685567] This should help authors understand how the "Name" field is going to be used.
Adds "Question #x" headers. [#48685567]
Fix report-button color [#48685567]
Specs for question_index.

Validates the value and that it respects reordering.
LightWeightActivitiesController#publish should make the activity 'public'

[#49161969]
https://www.pivotaltracker.com/story/show/49161969
Force sign-out-sign-in in LARA when launched from portal.

[#49166805]
https://www.pivotaltracker.com/story/show/49166805