Merge pull request #1651 from deepusudhakar/master

Escape $ZSH path in upgrade_oh_my_zsh

tools/upgrade.sh

 current_path=`pwd`
 current_path=${current_path/ /\\ }
 printf '\033[0;34m%s\033[0m\n' "Upgrading Oh My Zsh"
-cd $ZSH
+cd "$ZSH"
 
 if git pull origin master
 then