Strip old sqli example app and replace it with a simple login service

solvable/src/webservice/templates/internal.html

@@ -0,0 +1,9 @@
+{% extends "base.html" %}
+
+{% block content %}
+<h2>Welcome, {{session.username}}</h2>
+<p>You have successfully logged in</p>
+<a href="{{get_url('logout')}}" class="btn btn-default" >
+    <span class="glyphicon glyphicon-log-out"></span> Logout
+</a>
+{% endblock %}