Allow per project maxObjectSizeLimit.

Project owners can define receive.maxObjectSizeLimit in their
project.config in order to further restrict the global
receive.maxObjectSizeLimit setting from etc/gerrit.config.  The project
specific maxObjectSizeLimit is only honored if smaller than the global
maxObjectSizeLimit, otherwise it is ignored.

Change-Id: Ia14354e0c9b6bfb4fa62295162e8f2c127b09997
4 files changed