22 Checking VM Hardware Version: problem with v10 (ESXi 5.5)

Changed:

$vm.ExtensionData.Config.Version[5-6]

to:
$vm.ExtensionData.Config.Version.Substring(4)

https://github.com/alanrenouf/vCheck-vSphere/issues/65#issuecomment-26888052
Merge pull request #72 from craiggumbley/master

22 Checking VM Hardware Version: problem with v10 (ESXi 5.5)