Added NDJ/JSON reader
Added test data
slighlty better normalization in Marc21.get_sortable_author
Merge pull request #35 from jrochkind/ndj_reader

Ndj reader
marc21, putting code between comments and method breaks the rdoc, don't do that

Cc @billdueber
Merge branch 'master' into filing_chars
Fixed up extract_marc_filing_version
Add extract_marc_filing_version argument checking