Revert "Add heatmap tracker (crazyegg) to footer"

This reverts commit 8724938f6ef57b9e7c6b9688241ed4f1d66fbb1a.

Heatmap is done, we can disable the tracker now.
Merge pull request #132 from leobalter/revert-heatmap

Revert "Add heatmap tracker (crazyegg) to footer"