reverting upstream merge
Revert "Merge branch 'master' of git://github.com/ckaestne/TypeChef"

This reverts commit 08641ef3c72449f1b025e5abd055fac624679339, reversing
changes made to 635a01b8bbc5f741ee1848624bb816ca898d0653.
results of __real__ and __imag__ operations are assignable

Conflicts:
	CTypeChecker/src/main/scala/de/fosd/typechef/typesystem/CExprTyping.scala