skip if scanning for too long

See #434, release log:

• d55ab0e by @yegor256: #434 stop labels scanning too
• bc3138d by @yegor256: #434 stop if scanning for too ...
• 43980ca by @yegor256: shuffle
• cd7b915 by @yegor256: Merge pull request #432 from z...
• 499958e by @rultor: new version in README

Released by Rultor 2.0-SNAPSHOT, see build log