#16 add a dequeue button to build menu

[Simon]

if i click more then once on the build button the
builds are lined up but it is not possible to delete a
build from this line would be nice if that would work.
perhaps just with a right click on the build button.

and the metal that was used to this break would be lost
too.

mfg SirTwist

[Keith Turner]

Logged In: YES
user_id=28123

The user definetly needs a way to remove ships that are
scheduled to build.