Lots of fixes, some redesigning, and a new feature as well.

Fixed header, footer, etc.
Added the new Google+ link.
Revamped and validated donate page.
Various other fixes that I'm too tired to list.
Check the commits, I documented the changes extensively.
Here is a 90% zoom screenshot of the new donate page,
since I know you may be hesitant about changes to that page:
![selection_053](https://cloud.githubusercontent.com/assets/2244745/4586920/0346780a-5021-11e4-9720-67c55d5adb64.png)
Because I hadn't checked with any of you to see if that was okay or not.