Use the full path to wp-cli during provisioning

Something in the bash_profile changes caused our alias for wp to not be available during provisioning. We can use the full path during provisioning and still have `wp` aliased properly once things are setup.
Link /srv/www/wp-cli/bin/wp to /usr/local/bin/wp

This allows `wp` to be used freely without worrying about bash_aliases being loaded during provisioning. Worth keeping an eye out for consequences of this change, but it seems ok right now.
Update to CHANGELOG
Remove unnecessary sudo from provisioning

The provisioning script is being run as root, so there is no need to use sudo for any of the commands.
Remove stray  used to verify wp binary