Besu : Fixing DCO on master/release-

Created by Edward Evans, last modified by Felipe Faraggi on Jan 24, 2020

As a maintainer with Admin access to the repository:

  1. Clone an up-to-date version of the broken branch
  2. git commit --ammend --signoff  and ensure the appropriate Sign-off is included in the commit message
  3. Visit https://github.com/hyperledger/besu/settings/branches and change the glob to no-longer match the branch that is about to be force-pushed to
  4. git push --force-with-lease origin master 
  5. Return the branch protection glob to the old value
  6. Announce the change in the contributors channel a message like "The head of `master` branch for repository `hyperledger/besu` has been rebased to deal with a DCO issue, please follow the instructions on Fixing DCO on master/release- to fix your local repositories"

For everyone else:

  1. git fetch origin
  2. git branch -f master origin/master if your local master is based off the upstream master
  3. (Optionally) git push --force FORK master if you are keeping your fork's master up-to-date
  4. For all branches based on the bad checkout:
    1. git checkout $BRANCH 
    2. git rebase --interactive master 
    3. Remove the old master commit from the list