userscript: VPA-like object selection

done.

there're few glitches cause planets.nu object selection logic is still odd, but the overall functionality is pretty usable.

This small userscript makes map objects selection to be more VPA-like:

1. When you click on your own planet you always get planet view, not the list from the planet/ships orbiting.
2. When you already have an object selected and click somewhere, you have new object selected, if you want to set a ship waypoint or see a distance ruler click with Ctrl key pressed (automatic grav.well usage) or Alt key (grav.well will not be used)
3. Whenever you set a ship waypoint, gravity well is used automatically, and also a warp speed (maximum according to ship's engines)
4. If you don't want to use a warp well, or if you want to use manual waypoint inside a well, click with Alt pressed. Warp is always set automatically cause it's pretty rare case when you need to have non-maximum warp according to your engines (e.g. grav.well movement at 1 warp)