Improving error handling

[charly22]

• Improves the fetchadapter to handle non-JSON responses (like for TomTom APIs)
• Fixes error handling on Here geocoder, to parse ApplicationError type responses

[nchaulet]

Thanks for improving this 🚀

[nchaulet]

This seems to break some provider that return custom content type, I pushed a fix here https://github.com/nchaulet/node-geocoder/commit/5de7be0435ba2749096d1d30a2c2ea30ef71658a

[charly22]

@nchaulet thanks!