Add search box

Fixes https://github.com/theodi/shared/issues/201

Probably the last thing to merge, as we want to make sure the functionality works in the background before unleashing it to the public

![static dev templates dapaas html erb](https://cloud.githubusercontent.com/assets/109774/2862637/6273bf02-d1f7-11e3-9972-16f05ee57e80.png)