fix language error in initial setup page

At the step 1 of initial setup, in the sentence "If you want to add this server to an existing membase cluster select ....", I think there should be a comma between cluster and select (... cluster, select ...)
http://screencast.com/t/ZjMyM2I5O

Also in the step 2 of initial setup, I think we need to add "for" between account and this Server (account for this Server)
http://screencast.com/t/YTk4ZDQ4ZjU