Add a '--silent' switch to bash_it so it does not prompt for confirmation
Add a '--silent' switch to bash_it so it does not prompt for confirmation

- this means users profile automatically gets moved to a backup file, which is
  what we want in the standard case of running these scripts on a clean machine

jonsgreene/workstation-setup,jonsgreene/workstation-setup,pivotal/workstation-setup,pivotal/workstation-setup