add classLoader() method for classLoader aware environments
	modified:   src/main/groovy/org/nomin/Mapping.groovy
	modified:   src/main/groovy/org/nomin/core/ScriptLoader.groovy
	modified:   src/main/java/org/nomin/NominMapper.java
	modified:   src/main/java/org/nomin/core/Nomin.java
	modified:   src/test/groovy/org/nomin/core/NominTest.groovy
del