versionadded inside a warning in CrawlSpider docs

[wRAR]

https://docs.scrapy.org/en/latest/topics/spiders.html#crawlspider has a warning block that includes the "New in version" line.

Both indenting the warning block (not sure what's the best practice for the indentation here; also, XMLFeedSpider below has the same block which should have the same indentation I think) and moving versionadded before it (I think I don't like it) will work but I don't know which is the correct way to position these blocks.

[rudanov]

Hey! I am new here and I would like to take care of this issue.
I think the most correct way to do "New in version" block is how it's done here: https://docs.scrapy.org/en/latest/topics/request-response.html#scrapy.http.Response

A block in the beginning of the class description and additional block in the description of the attribute.
I also suggest changing marking of the attributes in CrawlingRules similar to Response docs:
link_extractor => .. attribute:: Rule.link_extractor