The sysprep parameters with the hidden attribute enabled are not
displayed to the user.

Add a mechanism in OSBase to add cleanup jobs. Use this mechanism to
cleanup the VirtIO drivers installation.

Add a method for disabling the first-logon animation. This will make
Administrator login faster if the Administrator account was previously
locked.

This is needed if the Administrator account is locked

This can be used to check if the media mounting was successful

Do not install and uninstall the winexe service in every single
execution of vm.rexec(). Only uninstall the service after executing the
last command which is either the sysprep or the shutdown command.

This used to be a sysprep but it is better if we disable it right away.
This is not needed for VMs and if this is enabled, the system will
hibernate on an ACPI shutdown event which will make the system
preparation to fail.

Make sure the guestfs handler is never cached in registry class. There
are cases where the guestfs handler is recreated in image class. The
registry code should always access the guestfs handler from the image
class and never from a local copy.

If we have verified that the OS in the Windows VM has booted, then wait
for a while to let it properly shut down even if an error occurred.

Display the return code and the stderr of the kvm process when the
customization VM dies unexpectendly

Do not upload the VirtIO drivers to %SystemRoot%\VirtIO. Use a temporary
directory for this job

Hide the powershell InstallDrivers.ps1 window if supported

Only install the drivers that where previously validated by
_fetch_virtio_drivers()

 * Detect the VirtIO driver type by the Device ID it refers to and not
   the catalog file name
 * Check if a driver is suitable for the input media by examining the
   TargetOSVersion field

When installing new drivers, make sure the old ones get uninstalled.

Rewrite the virtio_dir_check function that checks if a given directory
is indeed hosting VirtIO drivers.

Merge the Parameter menu entry with Sysprep and add a new entry for
installing VirtIO drivers. This will only be visible in Windows.

Collect more detailed information about the installed VirtIO drivers

Make install_virtio_drivers a public method of the class Windows

When installing the virtio drivers monitor the booting process of
the windows VM

Support installing virtio drivers in Windows 8, 8.1, 2012 and 2012R2

Remove mount and unmount methods and add a mount context manager for
mounting the media file systems.

This method can be used to compare the OS version against one specified
by the user.

Add a powershell script in the input media that will properly install
the virtio drivers in the next boot.

Upload the virtio drivers to the media and add the drivers directory to
the DevicePath Registry key

It is used many cases and it is better if we cache it.

Add this helper lambda function that can be used to update the value of
type REG_EXPAND_SZ

Add a dirty way to install the viostor driver in windows in order
to make them bootable. This works on Windows 2008R2

This parameter points to a directory that hosts virtio drivers for
windows.

Fix a bug where "$s" instead of "%s" was used in a string as a
placeholder.

This fixes #17

Small fixes and code beautification.

Extend the SysprepParam class to support defining a custom check
function which can be used to check if the value given by a user when
updating a sysprep parameter is valid.

Those lambda functions are used to set a value of type REG_SZ,
REG_DWORD and REG_BINARY in a registry node

This attribute hosts the block device associated with this Disk
instance. This can be the original media if the source media is a block
device, a loop device of the original media if the original media is a
regular file or a loop device of a temporary object if the original
media is a directory.

Changes include:

 * Break windows.py into multiple modules.
 * Rewrite sysprep parameters mechanism and add a menu entry for this
   in snf-image-creator expert mode.
 * Detect if the media is already sysprepped before performing further
   customizatog.
 * Don't ask for windows password before customization (reset it if needed)
 * Detect if the virtio drivers are installed in the media.
   If not refuse to perform the customization.

Use the @property decorator instead of the property() method to create a
read-only os attribute in Image class.

pep8 1.5 introduced a new test (E265) to ensure there's at least one
space before block comment.

Now that all sysprep parameters are optional, wizard page is no longer
needed.

Add a current_control_set property in Registry class. This way the
CurrentControllSet registry key is only computed once.