[Fix bug 1044790] Fix user availability form submission.

* Fix date parsing in datepicker initialization.
* Fix KeyError in availability form clean method.
[fix bug 1022393] Do not send inactivity notifications to unavailable users.
Merge pull request #792 from johngian/1044790

Fix form validation in user availability edit page.
Merge pull request #788 from akatsoulas/1022393

[fix bug 1022393] Do not send inactivity notifications to unavailable users.
[fix bug 1038644] Change the color of the edit voting button to grey.

* Move the vote button below the vote options.
Merge pull request #783 from akatsoulas/1038644

[fix bug 1038644] Change the color of the edit voting button to grey.