removed submodule rest-spec and prepared project for rest-api-spec instead of rest-spec
Add 'rest-api-spec/' from commit 'b3ab72486fae1b5c5a5397356a3e113bf72eb6d5'

git-subtree-dir: rest-api-spec
git-subtree-mainline: 7936d5496d8981b7136496c52185980357cc7fc6
git-subtree-split: b3ab72486fae1b5c5a5397356a3e113bf72eb6d5