Update appveyor.yml

New CI build logic

Merge pull request vgmstream#530 from bnnm/txtp-key

txtp key

Merge pull request vgmstream#516 from NicknineTheEagle/bugfix

EA MPF: Fixed SSX 3

Merge pull request vgmstream#510 from bnnm/fix

fix

Merge pull request vgmstream#506 from bnnm/fsb

fsb

Merge pull request vgmstream#493 from bnnm/xa-tests

xa tests

Merge pull request vgmstream#492 from bnnm/ogg-msadpcm-xa

ogg msadpcm xa

Fix planar format for mono files

Fix FFmpeg for non-planar formats