Log Message:
Add emulators/dosbox-x. Based on work by Yorick Hardy in pkgsrc-wip.

As a fork of DOSBox, DOSBox-X retains compatibility with the wide base of
DOS games DOSBox was designed for.

It also goes further, with a focus on accurate emulation of the hardware,
and many more ways to tweak and configure the DOS virtual machine.

The DOSBox-X team believes that a better way to emulate the legacy PC platform
is to give the user all the options they need to emulate everything from
original IBM PC hardware with 64KB of RAM all the way up to late 90's
hardware, whatever it takes to get that game or software package to run.