fix system dependency

Don't assume unix file system
Issue 711: MyBatis Generator Maven Plugin should log to Maven log

Fixes logging when log4j is not used.  The following error messages will
no longer seen:
log4j:WARN No appenders could be found for logger
(org.mybatis.generator.internal.db.DatabaseIntrospector).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for
more info.
Revert "fix system dependency"

This reverts commit a014b78a5d5302a82fb3259d783f4e6cd007ce4a.
Merge pull request #11 from paulkrause88/master

Issue 711:	MyBatis Generator Maven Plugin should log to Maven log