first changes for atari5200 target
add get_tv()
add some conio functions
use __RESERVED_MEMORY__ to reserve memory for the default 20x24 text screen
add gotox, gotoy, and gotoxy
Merge remote-tracking branch 'upstream/master' into a5200
Merge remote-tracking branch 'upstream/master' into a5200
atari5200 update: simple conio "hello world" works now
add dummy irq.s
add joystick driver -- trigger buttons are not queried yet
clrscr for Atari 5200 default conio screen
some CONIO fixes
changed version, startup screen now not fine anymore
documentation updates for Atari 5200
more documentation updates for Atari 5200
not a dummy implementation anymore...
Don't reserve space for display list in __RESERVED_MEMORY__ since the
default display list is in ROM.
more doc updates for atari5200
Merge pull request #121 from groessler/something_to_pull

small optimization
small doc update