Alphabetize private functions
Add specs and private doc headers
Refuse to start if java executable cannot be found

If the `java` executable cannot be found on the PATH then exit the
initialization process.
Add logging call

There appears to be some kind of race between shutdown and the stop
reason being logged. I added this additional logging call to make sure
the reason for shutdown is logged.
Merge pull request #265 from basho/refactor/rz/no-java-shutdown

Shutdown if java cannot be found on PATH