migrated to curator 2.5.0
STORM-213: fixed NullPointerException

* that was caused by submitting a topology to a LocalCluster with a decoupled ZK
fix the problem of log level implementation to compatible with old log protocol with no loglevel
Fix naming mismatch for twitter spout when building the topology for the print sample stream example
updated the pom.xml in storm-hdfs to be the correct version for
STORM-451
reportError when receiving an error-level message in ShellBolt.
Remove out of date comment

per worker heartbeating was introduced in Storm 0.8.0
update contributors list & change log for STORM-451
Merge branch 'curator-2.5.0' of https://github.com/devsprint/incubator-storm into STORM-453

STORM-453: migrated to curator 2.5.0
Merge branch 'master' of https://github.com/SeanTAllen/incubator-storm

Remove out of date comment
Added SeanTAllen to README
STORM-453: migrated to curator 2.5.0
Merge branch 'STORM-453'

Conflicts:
	README.markdown
Merge branch 'STORM-213' of https://github.com/wurstmeister/incubator-storm into STORM-213-fix

STORM-213: fixed NullPointerException
Added wurstmeister as contributor
Merge branch 'master' of https://github.com/mbeitchman/incubator-storm into STORM-458

STORM-458: sample spout uses incorrect name when connecting bolt
Updated Changelog and Readme for STORM-458
Merge branch 'shellbolt_reportfailedexception' of https://github.com/dan-blanchard/incubator-storm into STORM-455

STORM-455: Report error-level messages from ShellBolt children
Added STORM-455 to Changelog and README
Merge branch 'Multilang_JsonSerializer' of https://github.com/dashengju/incubator-storm into STORM-443

STORM-443: multilang log's loglevel protocol can cause hang