Added topic support to workspace.

* Fixes #1
* Made methods private
* Moved workspace directory to config
* Return errors for missing directories

Change-Id: Icec3865d2a518ae22721f14f4d562f9cb963b86b
Reset the merge conflict and continue attempting to build

Change-Id: I848d3831b99206a46f61f426670f485c46f28b02
Updated gowest to track previous build jobs.

Added support for cancelling a previous build job when an updated patch set has been submitted.

Fixes #2.

Change-Id: Ieed01a5f5be71c2ef6511f118d8eaed5c86a0ec4
Finish build-cancellation

* refs/heads/feature/build-cancellation:
  Updated gowest to track previous build jobs.