fix indentation
use a local copy of the grails zip file if it exists
optionally specify where to find a local copy of the grails zip
fail fast if grailsZipFileBasePath does not contain the expected grails zip
make logic around overriding grailsZipFileBasePath more consistent
Merge pull request #296 from forcedotcom/issues/296-optional-grails-zip

allow optional build parameter to rundeckapp to specify use of a local copy of the grails zip