This commit fixes loadufs command line to take parameters: bin/tachyon loadufs <TachyonPath> <UnderfsPath> [<Optional Excluding Prefixes;>]

(1) It adds a new method UnderfsUtil.getInfo/5 for implementing the new loadufs command line while keeping the old getInfo/4 for compatibility.
(2) It adds toString methods in PrefixList and TachyonFS for printing meaningful debug messages.
(3) It fixes list() in UnderFileSystemSingleLocal to return absolute paths, to be consistent with UnderFileSystemHdfs.
(4) It smooths out the uses of list() in other modules.
(5) It fixes docs/Syncing-the-Underlying-Filesystem.md accordingly.
auto-reformatted for code style
Added methods to CommonUtils

They come in handy across the code base
Fixed CommonUtils.concat check
polishing code style
More fixes to path manipulation functions
reformat code using the eclipse template
This commit makes the following fixes:

(1) It unifies under FS list() methods to conform to java.io.File.list(),
    which returns file paths relative to the given directory.
(2) It smooths out all usages of under FS list() for the above fix.
(3) It fixes the loadufs code with regard to the new list().
(4) It fixes the loadufs documentation accordingly.
Reimplemented path manipulation function to use Apache FilenameUtils

We make sure all the FilenameUtil functions use the UNIX path separator,
which equals Constants.PATH_SEPARATOR
fixed a few code style issues
Updated documentation
Merge pull request #169 from manugoyal/common-util-additions

Added methods to CommonUtils
rename UnderfsUtil getInfo() to loadUnderFs()
change local FS underfsAddress to /; fix a bug in excluding prefix-matching paths
how to run tests
Merge remote-tracking branch 'btachyon/master' into loadufs
add multiple signatures for loadUnderFs; allow for any levels of  exclude prefixes; update loadufs docs
polish loadufs code to use CommonUtils.concat
unit tests for methods implemented in this pull request
combine UnderFileSystemTest.parseTest cases