Add support for trivial publishing

Review Request #7762 — Created Nov. 9, 2015 and submitted — Latest diff uploaded

Information

RBTools
master

Reviewers

Both rbt publish and rbt post can now publish trivially. rbt publish does this via the --trivial flag and rbt post does this
via the --trivial-publish flag, which implies --publish. The trivial
indicator will only be sent when the server reports that it supports
trivial publishing via its capabilities.

Published a review request trivially with both rbt publish --trivial
and rbt post --trivial-publish.