Daemon server code to enable to cancel build.
Add --cancel option and cancellation that waits 10s for the build finish or does forcefulStop.

TODOs:
Need to add test coverage for stoping to verify daemon state after the operation.
Cancel through toolingApi has to cancel matching daemon rather than random one.
Fix 'can cancel action' test flakiness.
Cancel build using connection to a daemon asked to run the job.
Change cancel command to carry buildId.

This makes it safer that the right build is cancelled.
As a result --cancel option now has an argument (that needs to be searched in log).
Add integration test for command line invokation.