fixed typo

examples/dnn_imagenet_train_ex.cpp

@@ -4,7 +4,7 @@
     network used by the dnn_imagenet_ex.cpp example program.  
 
     You should be familiar with dlib's DNN module before reading this example
-    program.  So read dnn_inception_ex.cpp and dnn_introduction2_ex.cpp first.  
+    program.  So read dnn_introduction_ex.cpp and dnn_introduction2_ex.cpp first.  
 */
 
 

examples/dnn_introduction2_ex.cpp

 // The contents of this file are in the public domain. See LICENSE_FOR_EXAMPLE_PROGRAMS.txt
 /*
     This is an example illustrating the use of the deep learning tools from the
-    dlib C++ Library.  I'm assuming you have already read the dnn_inception_ex.cpp 
+    dlib C++ Library.  I'm assuming you have already read the dnn_introduction_ex.cpp 
     example.  So in this example program I'm going to go over a number of more
     advanced parts of the API, including:
         - Using multiple GPUs