Added search rules for finding license.xml. If license file is not
explicitly specified, the Server will look for 'license.xml' in the
working directory, followed by the directory of the jar file containing
the class VoltDB followed by the home directory.

If the file is found, a info message will be sent to the log indicating
the location where a working license file was found.
Change log from warning to info when default license file is found.
Merge remote-tracking branch 'origin/master' into ENG-5392-ChangeLicenseSearchPath
Merge pull request #1272 from VoltDB/ENG-5392-ChangeLicenseSearchPath

Eng 5392 change license search path