Add --field option for post command

Review Request #8429 — Created Sept. 23, 2016 and submitted — Latest diff uploaded

rbtools, reviewboard, students

This feature updates rbt post to allow for setting custom fields when
creating/updating a review request. It adds a new --field key=value
arguments, which would set extra_data.key=value in the payload. It
currently handles the native fields (description, testing_done,
summary) turning them into aliases of --description, --testing-done,
--summary. It also allows for multiple field arguments to be set

  • added --field description="desc" to an rbt post
  • Ensured that the field description contained "desc"
  • Added multiple fields --field description="high level desc"
    --field summary="short summary" to an rbt post
  • Ensured both argument fields were filled in correctly
  • Added Unit tests