Option to tell leaflet.draw to avoid touch screen behavior

[savage13]

Option added on Settings pane and in settings noTouchScreen

• Fixes clicking and dragging the map on polyline creation
• Modifies icon size on polyline creation and editing to be a reasonable size
  • Default is 8x8, touch icon is 20x20; this uses 12x12
• Patch overrides the _noTouch() function in Leaflet.Draw Polyline

There has been numerous discussions regarding Leaflet.Draw and its use of click events and attempting to use the presence of touch event to determine if a touch screen in present.

See: TouchExtend brakes map dragging (Leaflet.Draw) https://github.com/Leaflet/Leaflet.draw/issues/935#issue-446986829 L.Browser.touch should be retired (Leaflet) https://github.com/Leaflet/Leaflet/issues/6978#issue-554006348

[savage13]

Using L_NO_TOUCH as described at https://leafletjs.com/reference.html#global-switches makes it nearly impossible to click on the last point to finish drawing a polyline.