Name VHD/VDMK files based on name of box

[ideologysec]

as the title says, it would be great to name the vmdk/vhd/etc files after the name of the box if one is passed in, instead of hardcoding macinbox.

[bacongravy]

Sure, that seems reasonable.

[ideologysec]

controlled/set in cli.rb (L130-134), would also need an options.rb update:

@options[:image_path] = "macinbox.sparseimage"
@options[:vmdk_path] = "macinbox.vmdk"
@options[:hdd_path] = "macinbox.hdd"
@options[:vdi_path] = "macinbox.vdi"
@options[:box_path] = "macinbox.box"