ganglia: tweak settings for labs in eqiad

The Lucid instance hosting ganglia in labs did not survive the migration
(migrated as aggregator1 10.68.17.27 from 10.4.0.79).

Edits the ganglia labs to replace 10.4.0.79 with 10.68.16.101 and
probably get ganglia installed on hosts in eqiad (default_sites
updated).

Change-Id: Ifca6eaafa990a0567eee675f5386051e3a13181a