Add option for custom scale rendering

[victorzinho]

I am missing some flexibility for displaying the scales. I would like to do something like (using human-format):

map.addControl(new L.Control.SwitchScaleControl({
  ...
  render: ratio => '1 : ' + humanformat(ratio)
}));

What do you think?

[sonarcloud[bot]]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
2 Code Smells

No Coverage information
0.0% Duplication