Fix documentation (#2407)

Summary:
This commit fixes multiple issues with documentation.

https://output.circle-artifacts.com/output/job/23245537-e57b-4b9d-9b81-b3df20996d1f/artifacts/0/docs/tutorials/audio_resampling_tutorial.html

1. Duplicated requirejs
The nbsphinx extension introduced in https://github.com/pytorch/audio/pull/2393 pulled a requirejs
which caused the initialization script to halt.
As a result, the right side bar was left uninitialized.

2. Undefined variable error
It turned out that PyTorch's theme expected the downstream projects
to define `collapsedSections` variable.
Currently console log shows `collapsedSections is not defined`.
As a result of this fix, we start to see the + symbol on left side.

3. Fix the behavior of default expand
Tweaks the right-side bar initialization behavior
so that expand-all only happens once, not at every resize.

4. Overwrite the link to GitHub
The `GitHub` tab in main-menu always linked PyTorch core.
This commit adds overwrite to torchaudio page

Pull Request resolved: https://github.com/pytorch/audio/pull/2407

Reviewed By: carolineechen

Differential Revision: D36612904

Pulled By: mthrok

fbshipit-source-id: 56aa7623a8925a241cf4790ac77a87424ad9237c

docs/source/_templates/layout.html

@@ -54,7 +54,9 @@
 #}
 
 {%- block footer %}
-
+    <script type="text/javascript">
+    var collapsedSections = []
+    </script>
     {{ super() }}
     <script type="text/javascript">
       $(document).ready(function() {
@@ -69,8 +71,17 @@
 	      $(".pytorch-call-to-action-links a[data-response='Run in Google Colab']").attr("href", colabLink);
 	      $(".pytorch-call-to-action-links a[data-response='View on Github']").attr("href", githubLink);
 	  }
+
+          var overwrite = function(_) {
+              if ($(this).length > 0) {
+                  $(this)[0].href = "https://github.com/pytorch/audio"
+              }
+          }
+          // PC
+          $(".main-menu a:contains('GitHub')").each(overwrite);
+          // Mobile
+          $(".main-menu a:contains('Github')").each(overwrite);
       });
-    </script>
 
       {% if 'tutorial' in pagename %}
       {#
@@ -79,11 +90,12 @@
        # Based off of
        # https://github.com/pytorch/pytorch_sphinx_theme/blob/b4d00058a48604d8fb63771b513a50450f0ee188/pytorch_sphinx_theme/static/js/theme.js#L568-L579
        #}
-    <script type="text/javascript">
        $(window).ready(function() {
            var original = window.sideMenus.bind;
+           var startup = true;
            window.sideMenus.bind = function() {
                original();
+               if (startup) {
                    $("#pytorch-right-menu a.reference.internal").each(function(i) {
                        if (this.classList.contains("not-expanded")) {
                            this.nextElementSibling.style.display = "block";
@@ -91,6 +103,8 @@
                            this.classList.add("expanded");
                        }
                    });
+                   startup = false;
+               }
            };
        });
     </script>

docs/source/conf.py

@@ -54,6 +54,8 @@ extensions = [
     "nbsphinx",
 ]
 
+nbsphinx_requirejs_path = ""
+
 autodoc_member_order = "bysource"
 
 # katex options