message: Add note to try to sign commits
  CONTRIBUTING: add note to please sign commits
diff: @@ -22,6 +22,8 @@ Some Title
  - modify README to include Docs about A
  ```
  +and please sign your commits if possible
  +
  -> if you make fixing commits (like fixing a typo, fixing travis) use `git commit --fixup` (for autosquash)
  *Legend:*
  