add new Arc42 doc
Revert "add new Arc42 doc"

This reverts commit ef3c2bd459f4ecbb1d29d60c946ebc56c60dff4c.
Revert "Revert "add new Arc42 doc""

This reverts commit 12d0257a28e2833940ad02c40d44a3c6a91ecd71.
Merge branch 'master' of https://github.com/lightstalker89/MIT_SAD