Update FilterPaneService.groovy

Fixes jira issue 
http://jira.grails.org/browse/GPFILTERPANE-99
Update _filterpaneSort.gsp

Fixes jira issue 
http://jira.grails.org/browse/GPFILTERPANE-92
Upgrades to 2.2.1 and added maven pom to allow maven building
Suggested change to solve GPFILTERPANE-104

Makes it possible to supply your own valueMessagePrefix to a g:select while providing values to it.
Merge pull request #3 from ascheffe-umd/ars-2.2.1-upgrade

Ars 2.2.1 upgrade
Create README.md
Merge pull request #4 from stenix71/patch-3

Suggested change to solve GPFILTERPANE-104
Merge pull request #2 from stenix71/patch-2

Fix for GPFILTERPANE-92
Added tag filterPane and upgraded integration tests to Grails 2.x
Added tag filterPane and upgraded integration tests to Grails 2.x
Merge pull request #5 from stenix71/GPFILTERPANE-35

GPFILTERPANE-35
Adding travis-ci file
Removing broken service test and replacing with IntegrationSpec
Adding codenarc and code coverage plugins, git ignore and eclipse files
Incrementing the plugin version
Ooops travis grails version fix
Updating code narc to 0.18.1
Stupid grails 2.2.1 isn't pub'd to apt-get install yet.  Moving to 2.2.0 to accommodate travis-ci. *frown*
fixing pom to line up versions of plugins
Regenerating POM, seems to break travis-ci