Copy system properties to maven model request.
Merge pull request #492 from jdpgrailsdev/maven_jdk_activation_fix

JDK-based Maven profile activiation fix
exclude groovy-all as a transitive dependency from gpars

Pulling in another version of Groovy is causing problems...

Caused by: groovy.lang.GroovyRuntimeException: Conflicting module versions. Module [groovy-all is loaded in version 2.3.1-SNAPSHOT and you are trying to load version 2.1.9
Merge branch 'master' of github.com:grails/grails-core
Merge branch 'master' into groovy_2.3_jdk8