requirements.txt is not configured properly

the leading comment seems to cause an issue with pbr.
also adding in d2to1 and pbr versions to requirements.

Change-Id: I334d928b8a575522e3879f07d578be39890712b5
Fixes: bug 1192351
Move tests to ceilometerclient.

tests.* implies an incorrect global package name. Additionally,
consuming code can benefit from being able to choose to consume
test code and fixtures.

Change-Id: I7ba2b3ba1c2a99410b54fc40b48dfe2fc53eb79a
Merge "requirements.txt is not configured properly"