Adds support for admin to create flavors through mgmt API

Extending the management API to allow for an admin to
create flavors categorized on service type in trove.

Change-Id: I8d5910e6dd9e497d1a8be4ffd58aa339d12db74f
Implements: blueprint service-type-filter-on-flavors
Merge "Adds support for admin to create flavors through mgmt API"