[Feature Request] Leaflet.ExtraMarkers Plugin

[jaysnm]

Hi, much appreciations for this package.

In my day-to-day use of this package, I have come to realize that Leaflet.awesome-markers supported in the package hasn't been updated for a couple of years (upstream problem). In addition, markerColor parameter takes a set of pre-defined color values and has no space for hex codes (issue 89). This limits ability to brew colors subject to some conditions set forth by data processing/analysis, feed them into markerColor and map legend. Leaflet.ExtraMarkers plugin looks pretty cool with rich capabilities not supported by Leaflet.awesome-markers plugin.