MString updates.

testing/mstring_test.cpp

@@ -20,10 +20,12 @@ int main(int argc, char **argv) {
    coreutils::MString test4;
    test4 << "this is a test.";
    std::cout << "char* operator<<: [" << test4 << "]." << std::endl;   
-      
-//   coreutils::ZString temp("this is literal zstring data.");
-//   coreutils::MString test = temp;
-//   std::cout << "operator=: [" << test << "]." << std::endl;   
+
+   // String building tests.
+   coreutils::MString test5("/this/is/a/path");
+   coreutils::MString test6("/filename");
+   test5.write(test6);
+   std::cout << "test write: [" << test5 << "]." << std::endl;      
    
    return 0;
 }