Gradle/Grails app.version inconsistencies 

Steps to reproduce: 
 - Clean local maven repository, ivy cache, grails and gradle caches.
 - run "./gradlew -g $(pwd)/gradle-cache  -Penvironment=release -PreleaseTag=GA -PbuildNum=0 assemble"

This should cause a build failure.

Root cause is that the grails app.version (as defined in application.properties) is not necessarily the same as the gradle app.version. This causes rundeckapp build to fail because it can't find a rundeck-core-1.5.1-SNAPSHOT jar.

Please assign to me if accepted.