Use git worktree to maintain GitHub Pages branch

create_github_pages_branch.sh

# Initialize a gh-pages branch... GitHub expects this branch to exist to publish a project website from it.
git checkout --orphan gh-pages
git reset --hard
git commit --allow-empty -m "Initializing gh-pages branch"
git push origin gh-pages
git checkout master

# Define a directory where the static website files will reside 
WEBSITE_DIR=target

# Add a working tree for the new gh-pages branch (this allows us to work on the website without checking out that branch)
rm -rf $WEBSITE_DIR
git worktree add -B gh-pages $WEBSITE_DIR origin/gh-pages

# TODO build the website into the WEBSITE_DIR directory
<replace-this-with-the-commmands-to-build-the-website-into-WEBSITE_DIR>

# Publish the just-built website files
cd $WEBSITE_DIR && git add --all && git commit -m "Publishing to gh-pages" && cd ..