OCL Java code generator optimizes away the first condition "not self.container().oclIsUndefined()" because it thinks that "self.container()" can never be null although the return value is marked optional (assuming a bug in Pivot OCL)

(cherry picked from commit 113e8c05)

enabled OCL validation + Workaround for Complete OCL validator initializer configurator issue (see comment in code)

* fatjar build switched to package-single phase