Revert bogus change to json_object_get() made in f40b08d8 that caused it to always return NULL. (Issue #259)

Also undo NULL check in json_tokener_set_flags(): it's not at all valid toi
 try to set flags on a NULL pointer, and doing so should not be silently
 ignored.

json_object.c

@@ -172,7 +172,7 @@ extern struct json_object* json_object_get(struct json_object *jso)
 {
 	if (jso)
 		jso->_ref_count++;
-	return NULL;
+	return jso;
 }
 
 int json_object_put(struct json_object *jso)

json_tokener.c

@@ -979,5 +979,5 @@ struct json_object* json_tokener_parse_ex(struct json_tokener *tok,
 
 void json_tokener_set_flags(struct json_tokener *tok, int flags)
 {
-  if(tok) tok->flags = flags;
+	tok->flags = flags;
 }