Explicitly check if an object is a class is pydispatch.

* This is to fix a disagreement in between CPython and PyPy.
* https://gist.github.com/4220533
PEP8 on pydispatch/robustapply.py
doc: Response.replace() cannot take meta argument

>>> response.replace(meta={'foo':1})
Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "/srv/scrapy/scrapy-fork/scrapy/scrapy/http/response/text.py", line 45, in replace
    return Response.replace(self, *args, **kwargs)
  File "/srv/scrapy/scrapy-fork/scrapy/scrapy/http/response/__init__.py", line 77, in replace
    return cls(*args, **kwargs)
  File "/srv/scrapy/scrapy-fork/scrapy/scrapy/http/response/text.py", line 22, in __init__
    super(TextResponse, self).__init__(*args, **kwargs)
TypeError: __init__() got an unexpected keyword argument 'meta'
doc: remove trailing spaces
raise on unrecognized format
Merge pull request #307 from DeaconDesperado/raise-format

Raise a usage error when an invalid or unrecognized output format is entered on Command line
Add FAQ entry referencing Request.meta usage
Merge pull request #309 from amferraz/patch-1

Add FAQ entry referencing Request.meta usage
added test for bench command
Merge pull request #312 from nramirezuy/cmd/bech/test

added test for bench command
removed multispider support from logstats
use os.pathsep
simplify scrapy.tests.mockserver
removed multispider support, test added
Merge pull request #313 from nramirezuy/closespider-6017

drop multi-spider support from CloseSpider extension
test_closespider fixed for python 2.6
Merge pull request #311 from nramirezuy/logstats-6017

removed multispider support from logstats
obey request method when scrapy deploy is redirected to a new endpoint
merge 0.16.5 release notes
standarizes close_spider to use signals