Make the logging level of the collector configurable
Merge remote-tracking branch 'origin/pr/569' into develop
Bump src/collector

Bump cloudfoundry/collector:
  Serguei Filimonov:
     Merge pull request #15 from simonjohansson/fix-key-type ( Travis created: https://travis-ci.org/cloudfoundry/collector/builds/42689293 )
  Simon Johansson:
     Fix bug. ( Travis Unknown )
     Add failing test. ( Travis Unknown )