Add support for new patchset-created exclude fields

New exclude features added to Gerrit Trigger plugin version 2.12.0.

Exclude Features:
  - Drafts
  - Trivial Rebase
  - No Code Change

Change-Id: I923b0be47085dc50da48f5ed271a13eae7e1dfa0
Signed-off-by: Thanh Ha <thanh.ha@linuxfoundation.org>