Add beacon dial (will be needed for waypoints) and beacon label property

(beacon code isn't suitable as initial letter of label may differ from code: the N beacon being an obvious example)
Add dial to small HUD, slightly adjust normal HUD for better fit
Rearrange small HUD to give a little more space for ident block
Add beaconLabel properties to JS ship, visual effect

Note that we are now over half-full on ship properties, and fix resulting bug.
Adjust comm/console displays so there's room for later developments

Also stops a busy communications channel from running over the crosshairs.
Initial implementation of waypoints

Try something like this to test.
S.setWaypoint("test", { position: [3E5,3E5,0], size: 5000, beaconCode: "T", beaconLabel: "Waypoint 1" });
JS representation of waypoints

Change waypoint addition syntax to (label,position,orientation,definition) so that intuitive way of specifying position and orientation works.
Remove debug line
system.waypoints dictionary is readable
System highlight mode for long range chart
"reticle_scale" parameter for Scanner Targeting Enhancement

HUDs intended for large high-resolution screens may wish to reduce this a little from the default. Closes #20
The compiler might not complain, but it's still confusing to have two infos...
Make a start on the MFDs
JS support for setting MFDs

PS.setMultiFunctionText(key, string)
PS.setMultiFunctionDisplay(index,key)
PS.multiFunctionDisplays // count

Second function may end up as debug-only.
Keys for player to change MFDs

';' to change MFD content, ':' to select the next MFD if HUD has >1
':' now allowed as an SDL key, though more accurately shift-; now allowed
Add MFD to small HUD, make MFDs work after loading game
Adjust MFD sizes for better font scaling, force MFD lines to be right length.
Add polite way to request MFD display, deal better with over-long texts
Need to reset system data cache if galaxy (might) change
Waypoints now have distance shown if selection is active

(closes #12 as waypoints can now be used for long range indicators)