Problem: c_method_declaration in zproject_class_api is a bit messy
Problem: c_method_declaration in zproject_class_api is a bit messy

The "implementation_style" arg is not even used anywhere.

Solution: refactor and drop "implementation_style" argument.

asokoloski/zproject,hintjens/zproject,zeromq/zproject,paddor/zproject,taotetek/zproject,keent/zproject,paddor/zproject,paddor/zproject,zeromq/zproject,taotetek/zproject,eburkitt/zproject,twhittock/zproject,hintjens/zproject,asokoloski/zproject,taotetek/zproject,eburkitt/zproject,twhittock/zproject,keent/zproject,zeromq/zproject