refs #89: Added download disclaimer as modal popup window

refs #89: Added download disclaimer as modal popup window that shows on forms submit.  refs #91: Fixed issue with forms link in navbar

![screen shot 2014-06-16 at 8 40 05 pm](https://cloud.githubusercontent.com/assets/131928/3295135/e53275e4-f5b7-11e3-8202-9efb2dfd348d.png)