Lots more map work, mostly around switching from "construct a big HTML string"

to working directly with the DOM to update the table / selected plane info.
Seems to speed things up (and deflicker them) a lot.

Also stable sorts, allow disabling the clocks, draw ground tracks in a different
color, put "last seen" info on the selected plane infobox, if position updates
are infrequent then combine them into a single estimated line so that dash
placement works properly, probably a bunch of other things..

public_html/config.js

@@ -32,3 +32,6 @@ SiteCircles = true; // true or false (Only shown if SiteShow is true)
 // In nautical miles or km (depending settings value 'Metric')
 SiteCirclesDistances = new Array(100,150,200);
 
+
+// You can disable the clocks if you want here:
+ShowClocks = false;