MString edebugged.

ZString.cpp

@@ -81,6 +81,15 @@ namespace coreutils {
 	cursor  += length;
       return cursor - temp;
    }
+
+   void ZString::push() {
+      stack.push(cursor);      
+   }
+
+   void ZString::pop() {
+      cursor = stack.top();
+      stack.pop();      
+   }
       
    std::string ZString::str()
    {