Need to be able to specify failure issues by file

[nflorin]

The headless version of the validator needs to allow for failure issues to be set based on the needs of whatever program has put its files in the input folder. Since this might be multiple programs at once, each with their own set of issues, the validator needs to be able to set issues on a file-by-file basis.

[nflorin]

I think there are several things that need to happen:

• The config file needs to be switched from a flat configparser text file to something nested like YAML, so we can associate issues with specific files
• There needs to be a [DEFAULT] issue set that the regular interactive validator deals with, to the exclusion of the other issue sets (which won't normally be in the config file when the validator is not running in bulk/headless mode).
• The headless validator's helper script needs to add the nested issue sets to the config file as part of its run.
• The actual run of the validator needs to read file-specific issue data when it exists, and use the default when it doesn't.
• The helper script needs to remove the file-specific issue data when the headless run is over.

[nflorin]

This is now working for headless mode when issues are set in the bulk config file.