Add a help page that explains trial mode

> We start in trial mode and there are a bunch of things that we need to know, so
> let's explain this with a page, accessed from the footer. Not requiring log in.
> Should explain:
> 50 messages per day
> Can only send to yourself or team members
> How to go live
> We can then link to this from the dashboard (and any other place) where we
> tell you that you're in trial mode.

https://www.pivotaltracker.com/story/show/115775751

app/main/views/index.py

@@ -21,3 +21,8 @@ def verify_mobile():
 @main.route('/cookies')
 def cookies():
     return render_template('views/cookies.html')
+
+
+@main.route('/help')
+def help():
+    return render_template('views/help.html')