Do not change shell is zsh was not installed

install.sh

@@ -23,6 +23,7 @@ fi
 
 echo "Changing default shell"
 ZSH_PATH="$(which zsh)"
+if [ -x "$ZSH_PATH" ]; then
   if sudo -l chsh -s $ZSH_PATH $USER; then
     sudo chsh -s $ZSH_PATH $USER
   elif sudo -l usermod -s $ZSH_PATH $USER; then
@@ -33,6 +34,9 @@ else
       echo "Unable to change shell to $ZSH_PATH, please change shell manually"
     fi
   fi
+else
+  echo "No zsh available"
+fi
 
 SKEL_DIR="$APP_DIR/skel"
 BACK_DIR="$APP_DIR/backup"