create_hookup

PT#: 75024892: https://www.pivotaltracker.com/s/projects/982890/stories/75024892
Added a form on the hookups/index view for creating a new hookup (e.g. remote pair programming event)
This form can be shown/hidden with control by a button using javascript.
Javascript is tested via Cucumber features.
I'm still a jQuery novice, i.e. I know enough to be dangerous ;).  I'll find a pairing partner this week to improve this. Thanks for pointing out the problems.