refs #29 - added Casper.setHttpAuth()in urls

@@ -581,12 +581,7 @@
             // http auth
             var httpAuthMatch = location.match(/^https?:\/\/(.+):(.+)@/i);
             if (httpAuthMatch) {
-                this.page.settings.userName = httpAuthMatch[1];
-                this.page.settings.password = httpAuthMatch[2];
-                this.log("Adding authentication for user " + this.page.settings.userName, "info");
-            } else {
-                delete this.page.settings.userName;
-                delete this.page.settings.password;
+                this.setHttpAuth(httpAuthMatch[1], httpAuthMatch[2]);
             }
             this.page.open(location);
             return this;
@@ -686,6 +681,26 @@
         },
 
         /**
+         * Sets HTTP authentication parameters.
+         *
+         * @param  String   username  The HTTP_AUTH_USER value
+         * @param  String   password  The HTTP_AUTH_PW value
+         * @return Casper
+         */
+        setHttpAuth: function(username, password) {
+            if (!this.started) {
+                throw "Casper must be started in order to use the setHttpAuth() method";
+            }
+            if (!isType(username, "string") || !isType(password, "string")) {
+                throw "Both username and password must be strings";
+            }
+            this.page.settings.userName = username;
+            this.page.settings.password = password;
+            this.log("Setting HTTP authentication for user " + username, "info");
+            return this;
+        },
+
+        /**
          * Configures and starts Casper.
          *
          * @param  String   location  An optional location to open on start