Just my changes
Fixes #74, Fixes #75; proposal slide deck and tutorial handout support
Merge branch 'feature/lightning-talk-submission' into feature/75-75-upload-fields
Merge branch 'develop' into dans-styling-branch3
rendering new proposal fields and enabling markdown as HTML; Fixed #128
adjust Reviews for Lightning Talks, admin changes for lightning talks
Merge branch 'feature/75-75-upload-fields' into develop
Merge branch 'feature/128-talk-review-interface' into develop

Conflicts:
	symposion/templates/proposals/_proposal_fields.html
Start on tagging proposals

* Add tags field to ProposalBase
* Verify we can edit tags in the admin
* Display a proposal's tags in the reviews table, also in the proposal
  details on the review page
* Enable the reviews template context processor so we can navigate
  in the reviews area
* Add a form on the Reviews page to edit proposal tags.
Constrain memberships to uniqueness

Add constraint on (user, team)
Move review table help above table and mark for translation.
Merge branch 'feature/talk-tagging' into develop
Merge branch 'feature/133-dupe-memberships' into develop
Merge pull request #94 from caktus/dans-styling-branch3

Database & Association Pages
Merge branch 'develop' into staging