Fixed a 'malformed assignment' issue, read more

I've also added some support for compiler errors in general, but these
will get expanded on later.

I've also quickly added a valgrind option to the tests and found a few
leaks. I'll deal with these later.

Summary of changes:

* Clarified the lifetime of the bytecode in memory
* Erroneous routines exit without compiling
* Empty VMs don't run
* Added a check for malformed assignments
* Renamed "routine" to "module" within the VM
* VM no longer tries to free the bytecode - must be done manually
* Started experimenting with valgrind, not yet ready

repl/main.c

@@ -311,18 +311,19 @@ int repl(const char* filepath) {
 		}
 
 		Toy_Bytecode bc = Toy_compileBytecode(ast);
-		Toy_bindVM(&vm, bc.ptr);
+		Toy_bindVM(&vm, &bc);
 
 		//run
 		Toy_runVM(&vm);
 
 		//free the bytecode, and leave the VM ready for the next loop
 		Toy_resetVM(&vm);
+		Toy_freeBytecode(bc);
 
 		printf("%s> ", prompt); //shows the terminal prompt
 	}
 
-	//cleanp all memory
+	//cleanup all memory
 	Toy_freeVM(&vm);
 	Toy_freeBucket(&bucket);
 
@@ -531,7 +532,7 @@ int main(int argc, const char* argv[]) {
 		//run the setup
 		Toy_VM vm;
 		Toy_initVM(&vm);
-		Toy_bindVM(&vm, bc.ptr);
+		Toy_bindVM(&vm, &bc);
 
 		//run
 		Toy_runVM(&vm);
@@ -544,6 +545,7 @@ int main(int argc, const char* argv[]) {
 
 		//cleanup
 		Toy_freeVM(&vm);
+		Toy_freeBytecode(bc);
 		Toy_freeBucket(&bucket);
 		free(source);
 	}