Compatibility with Parallels provider

[legal90]

This commit adds compatibility with Parallels provider
I've checked it by myself and all existing features is working fine for this environment:

• Vagrant 1.4.0
• 'vagrant-parallels' v0.1.0
• Parallels Desktop 8 and 9
• Host: OS X 10.9
• Guest: Windows Server 2012 R2

P.s. I'm ready to support this compatibility in future.

[legal90]

Just one notice: while using Parallels provider, you should not put the forwarded_port rule into Vagrantfile, because our provider does not support port forwarding.
But provider is detecting guest's IP correctly, you can just skip this string and everything will work fine.

[sneal]

This change looks good, thanks!

Any idea if this would work with Parallels 7? I ask because that's the version I have.

[sneal]

Released vagrant-windows 1.5 gem with Parallels support.

[legal90]

Any idea if this would work with Parallels 7?

Unfortunatly, vagrant-parallels works only with Parallels Desktop 8 and higher. The reason is that prlctl utility in PD 7 has not option '--json' for machine-readable output and we have not done the backward compatibility yet (Parallels/vagrant-parallels#33).

[sneal]

That's OK, if I start using Parallels more often I'll probably upgrade it anyway.