Fix #50: Parser fails on external function without a return type
Fix #50: Parser fails on external function without a return type

AmesianX/DelphiAST,vintagedave/DelphiAST,RomanYankovsky/DelphiAST,NickRing/DelphiAST,LaKraven/DelphiAST,uschuster/DelphiAST,Wosi/DelphiASTTemp,monkeyxu/DelphiAST,Wosi/DelphiAST