Create pkg/machine/ignition package

Moves all of the ignitionfiles out of the `machine` package and into
its own called `ignition`. This required `VMType` to get moved out of
the `machine` package and into the `define` package in order to prevent
a circular dependency.

Signed-off-by: Jake Correnti <jakecorrenti+github@proton.me>

pkg/machine/pull.go

@@ -28,7 +28,7 @@ type GenericDownload struct {
 }
 
 // NewGenericDownloader is used when the disk image is provided by the user
-func NewGenericDownloader(vmType VMType, vmName, pullPath string) (DistributionDownload, error) {
+func NewGenericDownloader(vmType define.VMType, vmName, pullPath string) (DistributionDownload, error) {
 	var (
 		imageName string
 	)