implemented osm and leaflet
Merge branch 'master' of https://github.com/CodeforLeipzig/kidsle into DjangoFrontend

# By Max Brauer
# Via Max Brauer
* 'master' of https://github.com/CodeforLeipzig/kidsle:
  formatted playgrounds.json and added lat/lng
  added playgrouds.json
made markers for playgrounds and kitas visible on the map with custom markers
made layergroups for users to toggle markers
yeah filter workes in custum menu
updated color for palygrounds and replaced checkboxes by buttons
added leafletmarkercluster js but there seems to be a problem with the playground layer. there ist a duplicate of each item
the unknown commit
updated gitignore
well prepared for pull request
make things nice
Merge pull request #3 from CodeforLeipzig/DjangoFrontend

Merged Branch Django frontend into master