Add errors parameter in documentation.
Add errors parameter in documentation.

pawelmhm/scrapy,dangra/scrapy,pablohoffman/scrapy,dangra/scrapy,pawelmhm/scrapy,starrify/scrapy,dangra/scrapy,scrapy/scrapy,elacuesta/scrapy,starrify/scrapy,elacuesta/scrapy,starrify/scrapy,scrapy/scrapy,pablohoffman/scrapy,pawelmhm/scrapy,pablohoffman/scrapy,elacuesta/scrapy,scrapy/scrapy