Migrating trove to entry points

PBR/Distribute generates binscripts for us. By moving the
binscript code into the source tree, we can unit test it
as well. Run setup.py develop to generate the binscripts for
development use.

implements blueprint entrypoints-for-binscripts
Change-Id: I9ad4bb4ddc55f64bcd806c588a795cd6e0847aa9
Merge "Migrating trove to entry points"