Add an option to V2 submissions that expresses the maximum amount of time which this job can usefully spend in the Queue. If the job has not started within that time, the job will be canceled. If the option is not given, the job stays in the queue.

Document the use of this option - advise that the time period correlates with the lifetime of the build files for the job as well as the relevance of the results if the job is delayed too long.

See also LAVA-601 to try to minimise how often this step occurs.

Tag the job in such a way that a Query can be built which uniquely identifies all such jobs.

Migrated from https://projects.linaro.org/browse/LAVA-638