IE 11 fixes

The sticky footer and holy grail CSS appears to be broken in IE 11 (unless the version provided with my VM from https://github.com/xdissent/ievms is messed up). See screencaps.

I believe the reason is that IE has different default values for the `flex` property.

Not tested on earlier versions of IE.

![screen shot 2013-09-26 at 12 51 17 am](https://f.cloud.github.com/assets/816444/1215526/9837a188-2669-11e3-81e7-cffee8aa3c16.png)
![screen shot 2013-09-26 at 12 51 27 am](https://f.cloud.github.com/assets/816444/1215527/983956cc-2669-11e3-833e-eba12eba1da1.png)