cleaned up restroom signs & fixing/cleaning-up links and annoying mouse-over blips

Sorry if I'm stepping on anybody's toes by editing the restroom sign graphics, but they seemed a little choppy so I cleaned them up to reflect the RefugeRestrooms logo graphic, which incidentally brought down the file size by a factor of ten :) I used Inkscape to do all the editing, so everything is still infinitely scalable as svgs embedded in pdfs.

![commentary-on-creating-the-new-door-signs](https://cloud.githubusercontent.com/assets/299435/3488384/b3f4c09e-04e0-11e4-83ea-bff3e83a9a86.png)

And then the second part of this pull request: I resurrected a dead link to waffle.io in the README, updated some links to the old github.com/tkwidmer/refugerestrooms address for the repo, and fixed an issue to do with extra space in the html of the _footer causing a blip to appear to the right of each social icon on mouse-over.

![blip-problem-on-mouseover_github](https://cloud.githubusercontent.com/assets/299435/3488371/5d5483dc-04e0-11e4-896c-30c1e8e09362.png)
![blip-problem-on-mouseover_twitter](https://cloud.githubusercontent.com/assets/299435/3488374/5d5558c0-04e0-11e4-8516-96905ef20428.png)
![blip-problem-on-mouseover_facebook](https://cloud.githubusercontent.com/assets/299435/3488373/5d54b9c4-04e0-11e4-9f45-8fb60bc376af.png)
![blip-problem-on-mouseover_tumblr](https://cloud.githubusercontent.com/assets/299435/3488372/5d549822-04e0-11e4-8f58-691d22037100.png)
![blip-problem-on-mouseover_contact](https://cloud.githubusercontent.com/assets/299435/3488375/5d556b1c-04e0-11e4-9105-0478fc5d0822.png)

(I don't know how to split up the commits into two separate pull requests sorry, maybe I'll figure that out next time, especially if this request is rejected for being ill-documented/jumbled/etc. haha but cheers! :)