Fix race condition in start-up of salt-minion and salt-master

The last few days, I have been getting errors intermittently when using the salt bootstrap scripts where when it checks if both the salt-master and salt-minion are running when installed together on the master VM, one of the two daemons fails to start-up complaining that /var/log/salt already exists when it attempts to create /var/log/salt/minion or /var/log/salt/master directory.

To get around this issue, I install the salt-master and salt-minion in separate steps.  It has proven more reliable.