Rename admin/admin space to admin/monitoring.
Rename admin/admin space to admin/monitoring.

This mostly contains monitoring-related apps, so it makes sense to name
it accordingly. Other apps in this space are going to be moved
elsewhere.

alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf