Clean up remote git branch that are already merged into master

#may need to update local branches fist
git remote update origin --prune

# get all branches that are merged into release
# remove the origin/ prefix
# make sure we don't delete release, develop and HEAD branches
# remove them
git branch -r --merged origin/release | sed 's/origin\///' | grep -vwE "(develop|HEAD|release)$" | xargs -n 1 git push origin --delete

#for develop
git branch -r --merged origin/develop | sed 's/origin\///' | grep -vwE "(develop|HEAD|release)$" | xargs -n 1 git push origin --delete

# should preview the list first
git branch -r --merged origin/release | sed 's/origin\///' | grep -vwE "(release|develop|HEAD)$"


# clean up local branches that have already been merged to develop
git branch  --merged develop | sed 's/origin\///' | grep -vwE "(develop|HEAD|release)$" | xargs -n 1 git branch -d