(#352) allow open-ended dates in pandoc csl
(#352) allow open-ended dates in pandoc csl

egh/zotero-better-bibtex,maxxk/zotero-better-bibtex,egh/zotero-better-bibtex,egh/zotero-better-bibtex,maxxk/zotero-better-bibtex,maxxk/zotero-better-bibtex,egh/zotero-better-bibtex