[Issue #56] Added support for progress-style (PMC) logging activity
[Issue #56] 'client_id' renamed to 'machineIdentifier', fixed LoggingScrobbler.create_session to support progress-style logging activity
[Issue #56] Optimization to logging activity header matching so we only match the header once
Merge branch 'fix/issue-56' into develop
Changed "Unable to find client..." log entry severity to info
Bump to version 0.6.10-develop