Changes: * [improved parser and formatted warnings](https://github.com/ntessore/tidybib/commit/ae1d6a7379e7b90c3b26be5e8515d60e83d79597) * [sort entries with same pubdate by key in ascending order](https://github.com/ntessore/tidybib/commit/7a5ef1e5e40bb83f12a2423810ec28a2cb57500b)