Adding mac keyboard bindings

[ziveo]

This PR is adding missing mac keyboard bindings

[orangemug]

Hi @ziveo thanks for the pull request, much appreciated. How about using something like

const isMac = navigator.platform.toUpperCase().indexOf('MAC')>=0;
if(isMac) {
  // Mac bindings...
}
else {
  // Non mac bindings...
}

So we only bind for the environment we're interested in?

Ref: https://stackoverflow.com/questions/10527983/best-way-to-detect-mac-os-x-or-windows-computers-with-javascript-or-jquery

[orangemug]

Ah actually it looks like we can just use mod. See https://github.com/ccampbell/mousetrap/blob/fec446031c88cfcbd4cbdbfcc6c88f16fae4a50b/mousetrap.js#L135

[ziveo]

I think this will work

[orangemug]

Thanks @ziveo merging

[orangemug]

...also @ziveo if you have time please share what you're using Maputnik for over in ticket #164