atari800: Update to 4.2.0. Nice.

Version 4.2.0 (2019/12/28) - released at SILK

New Features:

    raw Pokey registers recording by Ivo van Poorten
    new platform supported: FireBee
    optional hiding of hidden files/folders in the UI file selector
    libatari800 (Atari800 as a library) by Rob McMullen
    R: device (many years old feature) enabled by default

Fixes:

    proper check if SDL joysticks are found (fixes #58)
    Portrait mode for Android (related to #41)
    RMW for Pokey
    Improved BASIC LST file loading (#55)
    ROM OS path changes handled better (#15)
    improved "Find ROM images" - now Atari800 reboots if necessary (#15)
    fixed an old bug which caused freezing in the UI on Falcon

New command line options:

    -pokeyrec and its children
    -atari_files (#29)
    -saved_files (#29)
    -kbdjoy0 -kbdjoy1 -nokbdjoy0 -nokbdjoy1 (#29)

Plus many Atari Falcon specific fixes and improvements by Mikro. This should be the most complete and bug-free Atari Falcon release in years, so enjoy! :)

(nia)