Revert "varnish: add Ganglia metrics for memory statistics"

Breaks Ganglia; revert now, retry later with a clearer head.

This reverts commit 0ffa1d431853ccaccfa27a44ee5cf5e7756e5320.

Change-Id: Id7b5c7044884f348ee52b3724d63925e56937506
Merge "Revert "varnish: add Ganglia metrics for memory statistics"" into production