Set Trove client package for F20/EL6/EL7

F20/EL6/EL7 package the Trove client as "python-troveclient".

backport: icehouse
Change-Id: Ia422c412baf5d5b2a405205bb5d57e77101074cb
Merge "Set Trove client package for F20/EL6/EL7"