Verify error line #s

Need to verify the recorded line numbers for errors is always correct.

At this point, errors in sub-records (e.g. under INDI.NOTE, INDI.NAME, etc) may have line numbers relative to the sub-record, *not* the file.

Also need to check sub-sub-records (e.g. INDI.NOTE.SOUR, etc).

No files, tests, or entry points are identified in issue #76. Trace GEDCOM error reporting for INDI sub-records and sub-sub-records, compare recorded line numbers with file-level positions, and verify the behavior across the examples named in the issue.

Written by the indexing model from the issue text.