LegoEntity parsing extra Action strings (#141)

* LegoEntity parse action string

* Reduced size assert for MxEntity

* remove override keyword for LegoEntity function

* Move global strings to new define.cpp file

LEGO1/extra.h

@@ -0,0 +1,21 @@
+#ifndef EXTRA_H
+#define EXTRA_H
+
+// Items related to the Extra string of key-value pairs found in MxOb
+
+enum ExtraActionType
+{
+  ExtraActionType_opendisk = 1,
+  ExtraActionType_openram  = 2,
+  ExtraActionType_close    = 3,
+  ExtraActionType_start    = 4,
+  ExtraActionType_stop     = 5,
+  ExtraActionType_run      = 6,
+  ExtraActionType_exit     = 7,
+  ExtraActionType_enable   = 8,
+  ExtraActionType_disable  = 9,
+  ExtraActionType_notify   = 10,
+  ExtraActionType_unknown  = 11,
+};
+
+#endif // EXTRA_H