Rich output support

[yschimke]

e.g. inline images (iterm only), play sounds, pretty print and colour JSON output.

stealable code

https://github.com/yschimke/oksocial-output/blob/master/src/main/kotlin/com/baulsupp/oksocial/output/ConsoleHandler.kt https://github.com/yschimke/oksocial-output/blob/master/src/main/kotlin/com/baulsupp/oksocial/output/iterm/ItermOutputHandler.kt