Updating geoserver external, fixes #571
Removing hardcoded version
Removing osbolete version change scripts, replaced with build/update-versions.xml
Adding details about what's new in 4.1.1
Fixing name of pg service on Centos (closes #592)
Linux installs use Tomcat not Jetty
Merge remote-tracking branch 'origin/4.1.x' into r4.1.1