Trying to fix HBase support issue in TACHYON-27
Optimize imports; reformat code style; improve javadoc; remove the commented code.
Linked to TACHYON-46 in Javadoc
Improve Javadoc comments
Merge branch 'master' of https://github.com/amplab/tachyon into createNonRecursive
createNonRecursive() should throw exception if parent directory doesn't already exist,  which is extremely important for HBase to do fencing of dead region servers properly.
Fix the bug mentioned in [TACHYON-66]

Fix the bug mentioned in [TACHYON-66] "The memory usage statistics is
not right when multi-user cache the same file and stops their
connection".
Change the synchronized range
TACHYON-71 Prevent Thrift exception from leaking out from MasterClient and WorkerClient classes.

Remove invalid JavaDoc "@throws TException" in method declaration.
Prevent leaking of Thrift exceptions (TException and its inheritance classes) to outside of MasterClient and WorkerClient classes because no
classes outside MasterClient and WorkerClient should know about Thrift services.
Small cleanup to remove empty finally clause in TFsShell class.
new example
[TACHYON-69] Removed local check in readRemoteByteBuffer since that check exists in the caller.
Merge pull request #356 from dcapwell/npe-remote

[TACHYON-69] Removed local check in readRemoteByteBuffer
Merge pull request #357 from hsaputra/TACHYON-71_cleanup_teexception

TACHYON-71 Prevent Thrift exception from leaking out from MasterClient and WorkerClient classes.
WorkerClient minor tweak
check connection before using mClient
Merge pull request #360 from shimingfei/WorkerClientFix

check connection before using mClient
Synchronize on final objects
Style
Update comments
Merge pull request #362 from calvinjia/tachyon-40

[TACHYON-40] Synchronize on final objects