Change $.post to this.post in the kernel js file

This makes it easy to override the post function for custom communication requirements.  Any replacement function, of course, needs to have the same semantics as $.post.

IPython/html/static/services/kernels/js/kernel.js

@@ -35,6 +35,7 @@ var IPython = (function (IPython) {
         this.username = "username";
         this.session_id = utils.uuid();
         this._msg_callbacks = {};
+        this.post = $.post;
 
         if (typeof(WebSocket) !== 'undefined') {
             this.WebSocket = WebSocket;
@@ -94,7 +95,7 @@ var IPython = (function (IPython) {
         params = params || {};
         if (!this.running) {
             var qs = $.param(params);
-            $.post(utils.url_join_encode(this.kernel_service_url) + '?' + qs,
+            this.post(utils.url_join_encode(this.kernel_service_url) + '?' + qs,
                 $.proxy(this._kernel_started, this),
                 'json'
             );
@@ -113,7 +114,7 @@ var IPython = (function (IPython) {
         $([IPython.events]).trigger('status_restarting.Kernel', {kernel: this});
         if (this.running) {
             this.stop_channels();
-            $.post(utils.url_join_encode(this.kernel_url, "restart"),
+            this.post(utils.url_join_encode(this.kernel_url, "restart"),
                 $.proxy(this._kernel_started, this),
                 'json'
             );
@@ -386,7 +387,7 @@ var IPython = (function (IPython) {
     Kernel.prototype.interrupt = function () {
         if (this.running) {
             $([IPython.events]).trigger('status_interrupting.Kernel', {kernel: this});
-            $.post(utils.url_join_encode(this.kernel_url, "interrupt"));
+            this.post(utils.url_join_encode(this.kernel_url, "interrupt"));
         }
     };