spider.log to pass keyword arguments into twisted log.msg
added --pdb command option to enable pdb debugger on failure.
updated release notes with previous commit
Added check so that genspider cannot create a spider with the same name as the project.
Merge pull request #244 from morty/master

scrapy genspider allows you to create a spider module with the same name as the project
Merge pull request #240 from llonchj/spider_log

spider.log to pass keyword arguments into twisted log.msg
doc: remove links to diveintopython.org, which is no longer available. closes #246
doc: fixed rst title
made scrapy/item.py pep8 compliant
added 502 to RETRY_HTTP_CODES
arg_to_iter: treat items the same way as dicts (ie. non iterables). fixes #248
arg_to_iter: replaced double call to isinstance with a single one. refs #248
remove debugging code
Log overriden Scrapy settings when Scrapy starts.

This is useful for debugging, to quickly find out which settings where
used for a specific spider run. dict settings are omitted for brevity.
DEBUG level is used for consistency with "Enabled
extensions/middlewares" lines (which share a similar purpose).
doc: fix typo in spider middleware
fetch command should catch IgnoreRequest exception
Merge pull request #257 from stav/cleanups

doc: fix typo in spider middleware
docs/contributing: added note explaining what Scrapy contrib is
Merge branch 'shell' of git://github.com/stav/scrapy into stav-shell
pluggable sub-commands for scrapy comand-line