create marstyle browserlist

[javierartero]

In browserlist they comment on how to generate one using a shareable configuration
https://github.com/browserslist/browserslist#shareable-configs

Example
https://github.com/WordPress/gutenberg/tree/trunk/packages/browserslist-config

How we use bootstrap as a framework seems to me that we could use the same configuration.

>= 0.5%
last 2 major versions
not dead
Chrome >= 60
Firefox >= 60
Firefox ESR
iOS >= 12
Safari >= 12
not Explorer <= 11

Here you can see the list of browsers.
https://browserslist.dev/?q=Pj0gMC41JSwgbGFzdCAyIG1ham9yIHZlcnNpb25zLCBDaHJvbWUgPj0gNjAsIEZpcmVmb3ggPj0gNjAsIEZpcmVmb3ggRVNSLCBpT1MgPj0gMTIsIFNhZmFyaSA%2BPSAxMiwgbm90IEV4cGxvcmVyIDw9IDEx

[davidgg]

let's do it