Adding constraints support to libraries is slightly more complex than
services as the libraries themselves are listed in upper-constraints.txt
which leads to errors that you can't install a specific version and a
constrained version.
This change adds constraints support by also adding a helper script to
edit the constraints to remove python-saharaclient.
Change-Id: Ie448db6f78865a3dddadf7dc659c7546a5e0fa72
fb803225f3