Add in OSM: iD -> with current center and zoom
change OverpassAPI query to get polygons (nodes, ways) ToDo: render polygons
add: render polygons and calc center
Merge remote-tracking branch 'dahoo/master'

Conflicts:
	app/app.js
Merge pull request #3 from dahoo/master

Add autocompletion
Merge pull request #4 from ThorstenHi/master

Polygons, autocomplete and a dynamic link to iD
Autoselect first entry, add placeholder text