Add FileUtils.

Add utility methods to atomically write an integer to a file and
to read the integer back from the file. These methods are meant
to be used to read and write epoch files.
Merge pull request #38 from m1ch1/atomic

Implement atomic file for proposed / acknowledged epoch files
FileUtils: Auto-close streams.
Merge pull request #39 from m1ch1/master

FileUtils: Auto-close streams.
Leader election implementation.
Merge pull request #17 from EasonLiao/election

Implement leader election
FileUtils: fix javadoc warnings.
Merge pull request #43 from m1ch1/master

FileUtils: fix javadoc warnings.
SimpleLog: fix javadoc formatting.
Merge pull request #44 from m1ch1/master

SimpleLog: fix javadoc formatting.
Refactor the Participant into a separate class.
Merge pull request #41 from EasonLiao/refactory

Refactory
introduce dummy log for testing.
Merge pull request #46 from EasonLiao/dummylog

Introduce dummy log for testing.