response.selector, response.xpath(), response.css() and response.re()
remove .re() shortcut
update docs
update spider templates
Remove "sel" shortcut from scrapy shell$

Use response.xpath(), response.css() or response.selector instead.
document shortcuts in TextResponse class
Ammend example nesting selectors
Restore and deprecate "sel" shortcut
Merge pull request #690 from dangra/kmike-response-selectors

Added docs response selector shortcuts