Use correct Compass version.

I ran into issues when installing compass-rails as it threw errors about the haml version needing to be updated to 3.1 when I was on haml 3.1. If I updated my haml version further, it then threw an error about modifying Frozen Arrays. I spent 2 hours tracking down that compass-rails was installing compass v1.0.0. If I removed that installed compass v0.12.6 everything worked fine.

So this PR is to block using compass v1.0.0.