Update "Welcome to".

* Change color,
* Change to Trebuchet MS,
* Move 16px to the left of letter 'k', and move 16px above.
Disable login button if loginForm is invalid.
Set default color to #9298a1 and font size to 13px.
Set color of footer to same as Already Have a Page?
Change distance between button and footer to 17px.
Change footer links.

* Change to About Us,
* Add mailto links,
* Decrease font size to 11px to fit on one page,
* Also, change font size to 11px for form prefix.
Change logo-container color to white.
Use default font for "Already have an account"?
Change side panel width from 26em to 33em.
Merge pull request #41 from vitaliyg/design-changes-to-modal-37

Design changes to modal 37