Use org.codehaus.gmaven instead of org.codehaus.groovy.maven.

See http://jira.codehaus.org/browse/MNG-4863
Works with both maven 2.2.x and 3.0.x.
Merge pull request #221 from landryb/fix-gmaven-plugin

Use org.codehaus.gmaven instead of org.codehaus.groovy.maven.
update INSTALL
update INSTALL
update INSTALL
update INSTALL
update INSTALL
update INSTALL - use packaged tomcat, it's simpler for first install
update INSTALL and README
update INSTALL and README
Merge remote-tracking branch 'origin/master' into ldapadmin