OHDF reporter plugin for InSpec

[wdower]

Ergo:

inspec exec profile -t <target info> --reporter ohdf:scan-results.hdf

MITRE SAF needs the ability to control output from InSpec to make sure we can change the OHDF schema and still be able to populate an OHDF file from an InSpec scan.

• We will need to be able to include Ohai data in an InSpec scan natively (Ohai is already in use for Chef Infra, but not in InSpec). We can likely use the ohai InSpec resource as part of the plugin. This will give us the ability to modify the OHDF schema to include target data about what a scan was run against using InSpec itself.
• We can likely borrow the Chef Automate plugin's approach to doing this, where we just use the JSON reporter to fill out the bulk of the OHDF reporter format, then call Ohai to return target information, and then add a few more fields to the returned JSON reporter data object.