Add PDS label file paths and manifest files as additional possible inputs

[al-niessner]

🗒️ Summary

Allow argument to any one or more of lidvid, label, and/or manifest.

⚙️ Test Data and/or Report

Unit tests pass as do test using manifest file (new test file). New help message:

Checks the search DB that all references exist. If the api-auth is
provided, then it will also check that the registry API also finds all the
references.

All arguments are either a lidvid, label, or manifest file.
   A lidvid must start with urn:nasa:pds:.
   A label must be a well formed PDS XML file.
   A manifest file is one item per line with an item being a lidvid or
label. Each line must be terminated by a LF.

Multiple arguments may be given in any order: 'urn:nasa:pds:foo::1.0
label.xml urn:nasa:pds:bar::2.0 manifest.txt'.

 -A,--auth-api <auth-file>          file with the URL and credential
                                    content to have full (all product
                                    states) read-only access to the
                                    registry API
 -a,--auth-opensearch <auth-file>   file with the URL and credential
                                    content to have full, direct read-only
                                    access to the search DB
 -h,--help                          show this text and exit
 -t,--threads <count>               process the lidvids in parallel
                                    (multiple threads) with this argument
                                    being the maximum number of threads
 -verbose,--verbose                 set logging level to INFO

An auth-file is either a text file of the Java property format with two
variables: 'url' and 'credentials'. The 'url' property should be the
complete base URL to the Registry Search endpoint or Search API, e.g.
'https://localhost:9876/base', and 'credentials' a path to a java property
file with the user name, password, and other credential information as
that used by harvest. Or it is an XML text file used by harvest with
<registry> containing the 'auth' attribute.

♻️ Related Issues

Closes #741

[nutjob4life]

Although this also has the Java exceptions "gotcha" (throws Exception) the rest of validate does too, so approved! 👍