Made DLIB_ASSERT and DLIB_CASSERT not kill the process when running inside a

MATLAB mex file.

dlib/error.h

@@ -254,6 +254,15 @@ namespace dlib
 
         void check_for_previous_fatal_errors()
         {
+            // If dlib is being use to create plugins for some other application, like
+            // MATLAB, then don't do these checks since it terminates the over arching
+            // system.  Just let the errors go to the plugin handler and it will deal with
+            // them.
+#if defined(MATLAB_MEX_FILE)
+            return;
+#endif
+
+
             static bool is_first_fatal_error = true;
             if (is_first_fatal_error == false)
             {