Add the ability to disable install

.gitignore

@@ -1 +1,2 @@
 variables.conf
+.disabled

install.sh

@@ -3,6 +3,11 @@
 run_directory=$(dirname "$0")
 user=$(whoami)
 
+if [ -f $run_directory/.disabled ]; then
+  echo "Installation is disabled. Exiting..."
+  exit 0
+fi
+
 echo "Copying Systemd units to system directory..."
 sudo cp $run_directory/systemd-templates/firefox-backup-.service /etc/systemd/system/firefox-backup-$user.service
 sudo sed -i -e "s/PH_USER/$user/g" /etc/systemd/system/firefox-backup-$user.service