New: Added Admin page (fixes #30)

fixes #30

Added .gittouch

> If src/admin/public/js/app.js doesn't exist, the site fails to load (404, can't GET /js/app.js). Reproduced on OS X and Debian Wheezy.

But app.js is still not part of the repo. Should I add it on gitignore ? or a build script?
That [doesn't seem to be true](https://github.com/gagle/node-properties#stringify)?

```js
properties.stringify ({
  a: [1, "a"],
  b: {}
});

/*
a = 1,a
b = [object Object]
*/
```