Add new pushplans tag

Push plans is the new tag that will replace plans
The plans tag has become ambiguous with the introduction of test plans

This PR is backwards compatibile with existing pull requests that still have the plans tag. All new requests show a Quick Tag of pushplans instead of plans, so eventually, all requests should have pushplans.

To remove backwards compatibility, the database should be scrubbed of tags containing the plans tag and then all plans tag code can then be removed safely.