Don't copy atom packages

[alichtman]

# Remove atom packages
atom_packages_path = os.path.join(backup_path, ".atom/packages")
print(atom_packages_path)
if os.path.isdir(atom_packages_path):
    sp.run("rm -rf {}".format(atom_packages_path))

Can remove packages after they're copied like this, but I don't want to copy them at all. Maybe rsync --exclude will solve this, once #31 is taken care of.