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 diskimage-builder.
Change-Id: I795800589ea1491efd0e489a38b60e6adf33e7f3
