Add GeoJSON leaflet example

Some GeoJSON fixes

Some GeoJSON fixes

Some GeoJSON fixes

Merge pull request mevdschee#542 from sebj54/fix-router-error

Add a default error in SimpleRouter

Merge branch 'master' of github.com:mevdschee/php-crud-api

Better support for SlimPHP

Merge pull request mevdschee#530 from mevdschee/psr7

Implement PSR-7, PSR-15 and PSR-17

Fix for mevdschee#523

Update README.md