Renemed all variables to fit into a namespace

Basically, all Toy varaibles, functions, etc. are prepended with "Toy_",
and macros are prepended with "TOY_". This is to reduce namespace
pollution, which was an issue pointed out to be - blame @GyroVorbis.

I've also bumped the minor version number - theoretically I should bump
the major number, but I'm not quite ready for 1.0 yet.

repl/lib_standard.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include "interpreter.h"
+#include "toy_interpreter.h"
 
-int hookStandard(Interpreter* interpreter, Literal identifier, Literal alias);
+int Toy_hookStandard(Toy_Interpreter* interpreter, Toy_Literal identifier, Toy_Literal alias);