fix(build:sass): increases numeric precision of sass compiler


Buttons now match the height of inputs, when using them as input groups.

Previous [pull request](https://github.com/yeoman/generator-angular/pull/500).
Merge pull request #518 from peerb/master

fix(build:sass): increases numeric precision of sass compiler
fix(Gruntfile): correct attribute quoting

Fixes #521
feat(app): upgrade to AngularJS 1.2.6

taco-salsafication!
v0.7.1