Allow alternative OSM tiles

[guillaumechauvat]

Is your feature request related to a problem? Please describe.
Right now the OpenStreetMap data is displayed in the "standard" OSM style. I would like to be able to choose alternative styles, such as CyclOSM, since I mostly use it for cycling.

Describe the solution you'd like
For example, more options in the menu to choose from, like adding a "CyclOSM" option in addition to "Street Map", "Satellite Map", etc.

Describe alternatives you've considered
The tile sources could also be completely customisable maybe

Additional context
Nextcloud Maps now:

openstreetmap.org: