[TACHYON-30] cephfs as under filesystem

This makes cephfs as a new under filesystem.

The unit test environment is created by vagrant, detailed information can be found at vagrant/README.md.

the patch to make tachyon_classpath optional went in, so thats not an issue now.  The java_home part might need to be synced with the main template though.

Not for this PR, but would it make sense to refactor gluster and ceph templates so they don't need to keep up to date with any change to the default template?