Enable use of override for session timeout in hours, fix captcha bypass bug. (#51)

* - Enable use of override for session timeout. This is more useful than having to hard-code and rebuild the code for the previous 4 hour limit. Just set environmental variable and start the app.
- Future work may involve breaking down into minutes, but this is a good minimum delivery to provide value to end-user/developer.

- Fixes bug in Captcha code by introducing new landing page. This is not a new go template, it's a separate HTML file because SRP - single reponsibility principle. Happy for this to be refacted after merging commit.

- Fix for including Docker 1.12 override has been removed for later PR.

* Merge

* Reinstate 'material' JS include'

* https for JS includes

* HTTPs for JS in bypass

www/assets/app.js

@@ -3,6 +3,14 @@
 
 	var app = angular.module('DockerPlay', ['ngMaterial']);
 
+    // Automatically redirects user to a new session when bypassing captcha.
+    // Controller keeps code/logic separate from the HTML
+    app.controller("BypassController", ['$scope', '$log', '$http', '$location', '$timeout', '$mdDialog', '$window', function($scope, $log, $http, $location, $timeout, $mdDialog, $window) {
+        setTimeout(function() {
+            var el = document.querySelector("#submit");
+            el.click();
+        }, 500);
+    }]);
 
 	app.controller('PlayController', ['$scope', '$log', '$http', '$location', '$timeout', '$mdDialog', '$window', function($scope, $log, $http, $location, $timeout, $mdDialog, $window) {
 		$scope.sessionId = window.location.pathname.replace('/p/', '');