Fixes client to send 0 for min/max size

Previously, if 0 is passed as the min_size or max_size for a
configuration, the Trove client would ignore it and not put it in the
dict making up the request body. This changes that code to explicitly
check if this value is not None instead of ignoring it if its zero.

Co-Authored-By: Craig Vyvial <cp16net@gmail.com>

Fixes bug: 1398995

Change-Id: I7f1d196b00a612365576bfb82fbfd35d647588d4
Updated from global requirements

Change-Id: Ieafe119fe7df2567794c1c85c270c8236fb623b1
Workflow documentation is now in infra-manual

Replace URLs for workflow documentation to appropriate parts of the
OpenStack Project Infrastructure Manual.

Change-Id: Ie62438c60d2087fa067e967a5e2b8ea8ee392e48
Merge "Workflow documentation is now in infra-manual"