[Freeciv-Dev] (PR#12898) Better unit keynav for laptops

["Vasco Alexandre da Silva Costa" <vasc@xxxxxxxxxxxxxx>]

<URL: http://bugs.freeciv.org/Ticket/Display.html?id=12898 >

Lots of people have complained about it, because they do not have a
numeric keypad. They should be using goto, but for that goto needs to
allow unknown tile destinations. That should be a separate ticket.

The regular arrow keys should also be allowed for unit movement, however
suboptimal they may be for not having diagonal directions. People are
just too used to them.

Proposed user-side design:
#1 Selecting the map widget allows using the arrow keys.
#2 Mouse over the map widget selects it automatically.

Kudos to Mike Kaufman for suggesting #2. We should implement both.