Corrected org.springframework.security dependency error (missing 3.2.0)

Error caused by spring-security 3.2.0 dependency on sprint-security-core:2.0 (From Peter Rice) See http://grails.1312388.n4.nabble.com/Spring-Security-2-0-RC-release-td4649905.html
Merge pull request #20 from Terry-Weymouth/ImperialBranch

Corrected org.springframework.security dependency error (missing 3.2.0)