Update OpenAustin.html

Switched google groups signup form to wufoo form
Update OpenAustin.html

Added copy adapted from Open Austin website
Update OpenAustin.html copy and link to wufoo interest form

Copy adapted from open-austin.org. Wufoo form created at 05132013 hack night.
Update Hackathon.html
Merge branch 'master' of github.com:khit/atx-civic-tech-expo-demo into khit-master

Conflicts:
	html/OpenAustin.html
	src/pages/OpenAustin.rhtml
Merge branch 'patch-1' of github.com:clairedunn/atx-civic-tech-expo-demo into merge
Moving Claire's changes over into the source rhtml.