Vagrant version check

Because Vagrant 1.3.3. uses `:mount_options` while lower uses `:extra`
Format code and use same method as VVV

Except for the :extra flag because VVV uses an array there, while that triggers error on my machine with Vagrant 1.2.2.
Merge branch 'master' of github.com:humanmade/Salty-WordPress
Add check around ssh.max_tries for Vagrant 1.2 and lower
Merge pull request #48 from jmslbam/master

Vagrant 1.3 compatibility