2.0.0

• add direction arrows + canvas support to "leaflet-distance-markers.js"
• add a testing "leaflet-ruler.js" library inside the libs folder
• remove babel, update rollup and make use of css var() in base themes
• update @tmcw/togeojson to 4.6.0
• dynamic import() for non critical js code (code splitting)
• heart rate and cadence example
• add custom chart handlers in order to use any other custom attributes (gpx extensions)
• general code cleanup (remove some legacy methods, events and options)