#51 update theme with url query parameter.

Also fixed a nested comment alternating style issue

app.js

@@ -93,6 +93,21 @@ if(config.use_compression) {
 
 app.use(cookieParser())
 
+const themeMiddleware = (req, res, next) => {
+  let themeOverride = req.query.theme
+  if( themeOverride) {
+    // Convert Dark to dark since the stylesheet has it lower case
+    themeOverride = themeOverride.toLowerCase();
+    // This override here will set it for the current request
+    req.cookies.theme = themeOverride
+    // this will set it for future requests
+    res.cookie('theme', themeOverride, {maxAge: 31536000, httpOnly: true})
+  }
+  next();
+}
+
+app.use(themeMiddleware)
+
 if(config.use_view_cache) {
   app.set('view cache', true)
 }