Fixed bug in processDeclaration, it was looking at 'currtSc' and it should be looking at the 'stack' instead, to avoid confution I changed 'currtSc' to 'scopeID'. Changed even more stuff from [a] to Seq a. Fixed bug where it would show twice a 'notdeclared' error. If we get 'Void' from an expression, an error was surely already raised by it, so we don't raise another one. changed peek return to Maybe a.