added cluster support
added logs and config for cluster support
modified the cluser support
cluster_metric.py
Merge pull request #124 from shaoshal/master

add Android RUM support to Naarad
updated cluster support
Update examples to use "-c" option for config. Update list of supported metrics
modified logger
updated cluster_metric
Remove linkedin specific metrics from Readme
Merge pull request #136 from SharadGandhi/readme_updates

Readme.md updates
updated
udpated code.
Merge pull request #127 from zhenyun/master

Cluster support
Merge pull request #137 from shaoshal/master

Implement optional Naarad return codes: the return code, if enabled, reflects the number of metric failures