bump loggregatorlib

1b33526 Merge pull request #6 from cloudfoundry/use-new-yagnats-wrappers
bc3c7c8 Merge branch 'master' into use-new-yagnats-wrappers
7b34425 Support new yagnats

automatic promotion by GoCD workflow Loggregatorlib/128 > UnitTests/1 > UnitTests