beta-9

Desperate stabilization efforts. :) Apart from overall stability,
we also added support for many games that do not work on FreeDOS.
Namely: TestDrive2, Tetris Classic, Elite Frontier, Empire Soccer,
Virtual Chess, Alone in the dark, Alpha Waves and more.
Around 70 commits with usual thanks to Andrew Bird.

• Implement int21/0x71a6 by the use of dosemu2's int2f/0x11a6 extension
• Port to FreeBSD, thanks to @PaddyMac for ssh
• Proper port of the fcb subsystem, with help and testing by @andrewbird
• Many fixes and extensions to compiler front-end
• Many improvements to freedos kernel for supporting games