Link [INFO] should really be [DEBUG].
Implement logging in WADL-tools.

XSL messages can now be directed to standard logs.  Test, use log4j.
A message should start with one of the items below:

[TRACE]
[DEBUG]
[INFO]
[WARNING]
[ERROR]

If it does then it will be sent the the appropriate log level.  If no
level is specified at the beginning of the line then WARNING is
assumed.
Merge pull request #101 from RackerWilliams/log

Initial implementation of logging