Scrapyrt

What's Changed
* Handling errbacks by pawelmhm in https://github.com/scrapinghub/scrapyrt/pull/158
* Make the errback handling method configurable by radostyle in https://github.com/scrapinghub/scrapyrt/pull/156

New Contributors
* radostyle made their first contribution in https://github.com/scrapinghub/scrapyrt/pull/156

**Full Changelog**: https://github.com/scrapinghub/scrapyrt/compare/v0.15.0...v0.16.0

* fix compatibility with Scrapy 2.11 on crawler object

* fix compatibility with scrapy 2.10 https://github.com/scrapinghub/scrapyrt/pull/150
* drop end of life pythons (3.6, 3.7)
* add python 3.11 support

* add support for specifying Twisted reactor in Scrapy settings or ScrapyRT settings, fixes https://github.com/scrapinghub/scrapyrt/issues/132
* drop Python 3.5 support
* add Python 3.10 support
* remove distutils call https://github.com/scrapinghub/scrapyrt/commit/4e4c6f5ab2306580401e05d295f1ed6f0f46a3e6
* README updates

* dropped Python 2 support
* tested with Python 3.8, 3.9, Scrapy 2.4+, add official support
* option to explicitly pass crawl arguments for spider by "crawl_args" argument to GET and POST endpoints
* bug fix when API was hanging on bytes returned from user spiders
* removed not needed and outdated dependencies such as demjson, six
* documentation lifting (readme.md page in pip and github)

* fixed bug resulting from fact that since version 19.2.0 Twisted expects http headers of string type
* removed outdated, unused logging code that relied on scrapy.log deprecated in Scrapy