Embedmap

@mberg I believe, it's OK now.
I am pretty satisfied with the UI although @rowo touch is awaited ; especially for a loading indicator.
It's all self-descriptive, so I'll let you play with it.
What could be added now:
* mini-map inside popup (didn't had time for this)
* actually delete points when a submission is deleted (if only sub at that location).
* convert added submission to a regular point.
* concat js/css: my attempts at this failed.

![screen shot 2013-07-31 at 5 53 54 pm](https://f.cloud.github.com/assets/57929/888310/dba17af0-fa0b-11e2-9e86-0efefb6af63f.png)

It's all in the `embedmap` branch and can be safely deployed since it's on a different URL: replace end of map url `/map` by `/map_embed`.