Improve dotfiles-update-modules script

Signed-off-by: Kare Nuorteva <kare.nuorteva@me.com>

Author: kare

bin/dotfiles-update-modules

@@ -1,12 +1,30 @@
 #!/bin/zsh
 
-cd
-cd .vim/bundle
-for a in `ls`; do
-    cd $a
-    git checkout master && git pull --rebase
-    cd ..
-done
-cd ~/.oh-my-zsh
-git checkout master && git pull --rebase
-cd
+function usage() {
+    echo "Usage: `basename $0` [-h] [-u]" 1>&2
+    echo "stash, update and add modules, commit and pop stash" 1>&2
+    echo "-u only update modules" 1>&2
+    exit 1
+}
+
+if [[ "$1" == "-h" ]]; then
+  usage
+fi
+
+if [[ "$1" != "-u" ]]; then
+  dotfiles stash
+fi
+foreach module (`ls -d ~/.vim/bundle/* ~/.oh-my-zsh`)
+  echo "Updating $module"
+  cd $module
+  git checkout master
+  git pull
+  if [[ "$1" != "-u" ]]; then
+    dotfiles add $module
+  fi
+end
+if [[ "$1" != "-u" ]]; then
+  cd
+  dotfiles commit -s -m "Update modules"
+  dotfiles stash pop
+fi