Resolved issue #546. Output format parsing from filename extension.
Added back `-t` option. If `--output-format` not defined parse from extension `--output`
Fix default value.
Add import os for crawl.
fixed typo
Added more verbose error message for unrecognized output format. PEP8.
Fixed XXE flaw in sitemap reader
Run testsuite with py.test
Fixed XML selector against XXE attacks
Added test against XXE attacks for Sitemap
Added resolve_entities to kwargs in SafeXMLParser
make scrapy.version_info a tuple of integers
 Trial functionality for running tests with pytest

  * Change current dir to tmp dir on each test run
  * Log twisted with test.log
Add py33 environment to allowed failures in travis-ci
Support doctest and __init__.py test discover in pytest
Ignore files with import errors on pytest test discover
Change function name so it does not mess up with pytest autodiscover
Fix httpcache doctest that assumed dictionary order
Ensure spiders module reload between spider manager tests
Merge pull request #676 from csalazar/fix_xxe_flaw

Fixed XXE flaw in sitemap reader