implemented new functions for using conditionalExpressions
fixed a few bugs in CDeclUse
added alex new test cases
added test files for the new test cases..
fixed an error where identifiers in assignments of optional enumerators were also renamed
Merge remote-tracking branch 'origin/master' into ldv-gen

Conflicts:
	CRewrite/src/test/scala/de/fosd/typechef/crewrite/DeclUseTest.scala
	CRewrite/src/test/scala/de/fosd/typechef/crewrite/IfdefToIfTest.scala