While not strictly required for basic running, the build id from the execution framework is the UUID required to render URLs to logfiles that we need for reporting.

Using the build id to render log urls is covered by #122 but that doesn't cover how to get the build id needed for rendering those log urls.

The runner needs to support a build id as an argument but not require the build id for operation.
* Add a build id param to the cli entry used by buildbot
* Have a reasonable default for the local runner case so that the build id exists but is obviously a dummy value (0 or 9999999 might work)