Add initial index html and login procedure

- Add initial HTML to the index page for the admin and timetable tenant
    - Header
    - Sub header
    - Sidebar
    - Content
- Add a login form to the header and enable signing in and out
- Get the `/me` data when the page is initialising
- Create a `renderTemplate` function that takes a template, data and a target as arguments
- CasperJS and Qunit tests for the above
Minor thingy; do we need to use a dot at the end of the parameter description? We should be consistent and either use it everywhere if it's the last sentence or remove it anywhere. WDYT?

```
* @param  {Object}    object      This is a first sentence. This is a second sentence
* @param  {Object}    object      This is a first sentence
* @param  {Object}    [object]    This is a first sentence. (optional)
* @return {Object}                The returned value. Something extra