feat: add Open Cycle Maps

[ykorzikowski]

This PR will add the possibility to set the map type to opencycle maps. It requires free registration at Thunderforest.

The API Key provided need to be set as environment variable:

PUBLIC_THUNDERFOREST_API_KEY=<api_key>

[ykorzikowski]

I fixed the typo and added some docs how to set up the integration with thunderforest :)

[schmic]

Why not use the tiles from CyclOSM and avoid having to set up a Thunderforst API key?

1. 'https://a.tile-cyclosm.openstreetmap.fr/cyclosm/{z}/{x}/{y}.png',
2. 'https://b.tile-cyclosm.openstreetmap.fr/cyclosm/{z}/{x}/{y}.png',
3. 'https://c.tile-cyclosm.openstreetmap.fr/cyclosm/{z}/{x}/{y}.png'

[bebablub]

Why not use the tiles from CyclOSM and avoid having to set up a Thunderforst API key?

1. 'https://a.tile-cyclosm.openstreetmap.fr/cyclosm/{z}/{x}/{y}.png',
2. 'https://b.tile-cyclosm.openstreetmap.fr/cyclosm/{z}/{x}/{y}.png',
3. 'https://c.tile-cyclosm.openstreetmap.fr/cyclosm/{z}/{x}/{y}.png'

Good point thank you @schmic Was not aware that this map provider exists. It has more and detailed maps than open cycle map 👍

[Flomp]

Added in v0.18.0.