Useful update commands for Mac

# Get OS X Software Updates, and update installed Ruby gems, RBENV, Homebrew, npm, and their installed packages, and oh_my_zsh

alias update='sudo softwareupdate -i -a; brew update; brew upgrade --all; brew cleanup; npm install npm -g; npm update -g; sudo gem update --system; sudo gem update;rbenv rehash;upgrade_oh_my_zsh'