Initial implementation of twitter card functionality
Add twitter card to mapinfo.html
fix reference to map
Merge remote-tracking branch 'jj0hns0n/issue-500'

Conflicts:
	templatetags/mapstory_tags.py
profile form - email to top and required
make activity tag return blank
Merge branch 'master' of github.com:opengeo/mapstory
fix broken test from e66e0fd0