Swap P, semicolon and apostrophe

README.md: Tested on Debian 11

Remove indent on code blocks

Fix US layout (swap I and O back)

Document setxkbmap commands

Add kalamine file for the IO variant

Move asth-neoi.json into contrib

Add X11 installation method

Document some known design flaws

Add mailing list for patches

Add gb variant and kalamine install instructions

Add layout diagram PNG and JSON

The JSON data can be imported into keyboard-layout-editor.com

Hyphenate ASTH-NEOI

Initial commit