Create a directory to hold Git hooks

mkdir -p ~/.git_template/hooks/

Add This file to ~/.git_template/hooks/prepare-commit-msg

#!/bin/sh

if [ -z "$BRANCHES_TO_SKIP" ]; then
  BRANCHES_TO_SKIP=(master develop)
fi

BRANCH_NAME=$(git symbolic-ref --short HEAD)
BRANCH_NAME="${BRANCH_NAME##*/}"

BRANCH_EXCLUDED=$(printf "%s\n" "${BRANCHES_TO_SKIP[@]}" | grep -c "^$BRANCH_NAME$")
BRANCH_IN_COMMIT=$(grep -c "\[$BRANCH_NAME\]" $1)

if [ -n "$BRANCH_NAME" ] && ! [[ $BRANCH_EXCLUDED -eq 1 ]] && ! [[ $BRANCH_IN_COMMIT -ge 1 ]]; then
  sed -i.bak -e "1s/^/[$BRANCH_NAME] /" $1
fi

Make the file executable

chmod a+x ~/.git_template/hooks/prepare-commit-msg

Tell Git where to find the hooks

git config --global init.templatedir '~/.git_template'

To add the custom hook to a project

navigate to the project, then:

git init

Or run it for all applications together:

cd ~/src
for dir in *; do cd $dir; git init; done