Added ZString constructor for assignment on definition.

MString.h

@@ -40,6 +40,8 @@ namespace coreutils
       MString(const char *data, size_t length);
       
       MString(const unsigned char *data, size_t length);
+
+      MString (ZString zstring);
       
       ///
       /// Consructor providing a copy of a ZString.