Added dictionary support to OP_ITER

ISTRING_RESERVED was added to iStrings
call & callCFunction now use memmove instead of memcpy
Additionally, added cosmoO_setUserP, cosmoO_getUserP, cosmoO_setUserI and cosmoO_getUserI to the C API.

src/cstate.h

@@ -20,6 +20,7 @@ typedef enum IStringEnum {
     ISTRING_SETTER,     // __setter
     ISTRING_ITER,       // __iter
     ISTRING_NEXT,       // __next
+    ISTRING_RESERVED,   // __reserved
     ISTRING_MAX
 } IStringEnum;