Update the main images to overview page in profiling tutorial. (#3372)

* minor updates to tutorial

* minor updates to tutorial

* minor update

* Fix article

Author: qiuminxu

docs/images/profiler_overview_page_bad_ip.png

@@ -376,19 +376,19 @@
         "colab": {}
       },
       "source": [
-        "%tensorboard --logdir=logs"
+        "%tensorboard --logdir=logs  # Navigate to the profile tab to view performance profile."
       ],
       "execution_count": 0,
       "outputs": []
     },
     {
       "cell_type": "markdown",
       "metadata": {
-        "id": "o6jbOkSp7VoO",
+        "id": "Q2rhYXT2WAyt",
         "colab_type": "text"
       },
       "source": [
-        "<img class=\"tfo-display-only-on-site\" src=\"./images/tb_call_1.png\"/>"
+        "<img class=\"tfo-display-only-on-site\" src=\"https://github.com/tensorflow/tensorboard/blob/master/docs/images/profiler_overview_page_bad_ip.png?raw=1\"/>"
       ]
     },
     {
@@ -541,7 +541,7 @@
         "colab_type": "text"
       },
       "source": [
-        "Re-launch TensorBoard to observe the performance profile for the updated input pipeline. "
+        "Re-launch TensorBoard and open the profile tab to observe the performance profile for the updated input pipeline. "
       ]
     },
     {
@@ -564,7 +564,7 @@
         "colab_type": "text"
       },
       "source": [
-        "<img class=\"tfo-display-only-on-site\" src=\"./images/tb_call_2.png\"/>"
+        "<img class=\"tfo-display-only-on-site\" src=\"https://github.com/tensorflow/tensorboard/blob/master/docs/images/profiler_overview_page_good_ip.png?raw=1\"/>"
       ]
     },
     {