Adstex

1. Incorporateing 49 implemented by birnstiel , enabling coauthors in the ADS search if the citation key has the format of `firstauthor:coauthor1:coauthor2:year`. However, to avoid breaking backward compatibility, this feature is disabled by default and need to be enabled with the argument `--use-coauthors`.

2. To reduce the hassle of specifying `--use-coauthors`, or other optional arguments, every time, this version also introduce a new feature to set an environment variable `ADSTEX_ARGS` for default arguments. For example, setting the following in `.bashrc` will always enable the coauthor and parallel features.
bash
export ADSTEX_ARGS="--use-coauthors --parallel"


What's Changed
* update python versions by yymao in https://github.com/yymao/adstex/pull/50
* include co-authors in search query by birnstiel in https://github.com/yymao/adstex/pull/49
* v0.6.0: coauthor and default option features by yymao in https://github.com/yymao/adstex/pull/51

New Contributors
* birnstiel made their first contribution in https://github.com/yymao/adstex/pull/49

**Full Changelog**: https://github.com/yymao/adstex/compare/v0.5.4...v0.6.0

What's Changed
* Change the ADS first author query by yymao in https://github.com/yymao/adstex/pull/48


**Full Changelog**: https://github.com/yymao/adstex/compare/v0.5.3...v0.5.4

What's Changed
* bugfix for merge-other by syrte in https://github.com/yymao/adstex/pull/45


**Full Changelog**: https://github.com/yymao/adstex/compare/v0.5.2...v0.5.3

This release allows fetching nonstandard entries (such as `software`) as suggested by kirxkirx in 42.

What's Changed
* allow nonstandard entries by yymao in https://github.com/yymao/adstex/pull/43


**Full Changelog**: https://github.com/yymao/adstex/compare/v0.5.1...v0.5.2

This PR fixes a bug of bib file not being updated when using adstex with bibtexparser v1.4.1. Thanks to stevenrjanssens for reporting the issue.

What's Changed
* make compatible with bibtexparser v1.4.1 by yymao in https://github.com/yymao/adstex/pull/39
* make lower case -p acceptable by yymao in https://github.com/yymao/adstex/pull/40


**Full Changelog**: https://github.com/yymao/adstex/compare/v0.5.0...v0.5.1

A new option `--parallel` (or `-P` for short) is introduced to enable parallel execution of `adstex` to speed things up. This new option is *not* enabled by default. When `--parallel` is set, `adstex` will use 8 threads to look up the references. One can adjust the number of threads by setting `--threads=x`.

Thanks to dwijn for suggesting and implementing this new feature.

**Full Changelog**: https://github.com/yymao/adstex/compare/v0.4.0...v0.5.0