Fix the error
```homestead-7: Creating and registering the VM...
An error occurred while executing a PowerShell script. This error
is shown below. Please read the error message and see if this is
a configuration error with your system. If it is not, then please
report a bug.
Script: import_vm_vmcx.ps1
Error:
At C:\Program Files
(x86)\HashiCorp\Vagrant\embedded\gems\gems\vagrant-1.9.4\plugins\providers\hyper v\scripts\import_vm_vmcx.ps1:18 char:37
+ [string]$differencing_disk=$null
+ ~
Missing ')' in function parameter list.
At C:\Program Files
(x86)\HashiCorp\Vagrant\embedded\gems\gems\vagrant-1.9.4\plugins\providers\hyper v\scripts\import_vm_vmcx.ps1:20 char:1
+ )
+ ~
Unexpected token ')' in expression or statement.
+ CategoryInfo : ParserError: (:) [], ParseException
+ FullyQualifiedErrorId : MissingEndParenthesisInFunctionParameterList
```
It was failing to create files below the machines\default\hyperv folder, rather it was creating folders named 'hypervSnapshots', 'hypervVirtual Hard Disks', and 'hypervVirtual Machines'. This was causing the files to not be removed when destroying the vm, and an error when subsequently bringing it up again.
Implemented the differencing disk for vmcx.
This means the disk is now copied by Hyper-V (Powershell) instead of Ruby for new machines.
This does mean EFI Firmware now does work for machines since it is quite a feep copy. Compare-VM will report incompatibilities should they be found.
Chris Roberts
Arjan Weurding
Bjorn Brala
Brian Retford
Jake Ballard