Merge pull request #32 from calvinjia/master

Fix UI Bug
allow to show partial data.
fix ui bug.
sort the node info by host name
fix compile for hadoop 2
fix a parameter name in template config.
fix unmount issue in Mac OS X
Merge pull request #33 from cybermaster/master

fix unmount issue in Mac OS X
write ch plus various fixes.
Merge branch 'master' of github.com:amplab/tachyon
mkdir returns true/false
use master hostname in conf/tachyon-env.sh as default.
show disk usage
user NoWorkerException instead of NoLocalWorkerException
fix null pointer bug in blockinstream
add replication and blocksize parameter to underfs interface.
temp fix for replication factor for hdfs
fix of bin/start.sh hangs by redirecting output to the null device.
Merge pull request #36 from hobinyoon/master

fix of bin/start.sh hangs by redirecting output to the null device.
fix of the bin/format.sh error.