add checksum and filetype to report

[saselberg]

Hi,

I work for Keysight Technologies. We're creating a tool to create an inventory of the various security related properties of the files. We've been asked to collect the checksum and filetype in addition to the information your tool is collecting. Would you be open to accepting a PR adding the checksum and filetype based on command line flags? For the file type, I would use the python-magic library which will introduce a depencency you may or may not be comfortable with so I wanted to call that out.