Configurable network labels used for showing IPs in instance details

The ip shown in the instance detail was hard coded to be obtained from
a nova netwok label 'private' or 'usenet'. With this change, the labels
is configurable based on a regex pattern.

Fixes bug 1206303

Change-Id: I73d896e6b85bdebe342a777219b9b60d6954f8b6
Removing mycnf static files from contrib.

implements bp guestagent-mycnf-versioning

Change-Id: I4ad06d165b47be49841a83de2d1d229cd7561775
Fixing bug in Interrogator tests mocks.

Change-Id: I474c4469842bd5e68632d49a2b4711beeae06128
Merge "Fixing bug in Interrogator tests mocks."
Merge "Configurable network labels used for showing IPs in instance details"
Merge "Removing mycnf static files from contrib."
Merge branch 'master' of https://github.com/openstack/trove