Introduce all_articles where articles is shadowed.
update the docs regarding all_articles
Make METADATA_PROCESSORS and EXTENSIONS public.
readers: Split parse_path_metadata from read_file

For easier re-use.  I also extract the path metadata first, so
metadata explicitly listed in the file contents will take precedence
over metadata parsed from the filename.
Add the PATH_METADATA setting

Sometimes the base filename doesn't have everything you need.

Remember that os.sep is platform dependent, so using it in a regular
expression for this setting may not be portable (boo MS Windows!).
contents: Add URLWrapper.__repr__

This makes it easier to troubleshoot collections of URLWrappers,
because printing the collection will give you something you can
actually read ;).
Merge pull request #771 from wking/urlwrapper-repr

contents: Add URLWrapper.__repr__
Add a period archives feature and brief docs.

Allows users to have per-year, per-month, and per-day archives of posts
automatically generated. The feature is disabled by default; to enable
it a user must supply format strings for a period's respective
`_SAVE_AS` setting.
External resources should be scheme-independent

By using "//" instead of "http://" when referring to external resources
such as fonts (e.g., from within CSS files), warnings about "insecure"
content can be avoided.
documentation for IGNORE_FILES
Added missing JINJA_FILTERS documentation
Added missing SITESUBTITLE documentation
Fix typos
Merge pull request #779 from johnmastro/add-period-archives

Add period archives
Merge pull request #785 from wraithan/docs_for_ignore_files

documentation for IGNORE_FILES
Fix typos
Merge pull request #786 from noirbizarre/more-documentation

Add missing documentation for JINJA_FILTERS and SITESUBTITLE
Add help directly to publishconf.py
Merge pull request #791 from wraithan/add_some_help

Add help directly to publishconf.py
Replace os.sep.join with the more robust os.path.join

From the Python docs for os.sep [1]:

  Note that knowing this is not sufficient to be able to parse or
  concatenate pathnames - use os.path.split() and os.path.join()...

Where I touched a line, I also changed double quoted string literals
to single quotes, since they are used more often in the source:

  wking@mjolnir ~/src/pelican $ git grep "'" pelican/*.py | wc -l
  683
  wking@mjolnir ~/src/pelican $ git grep '"' pelican/*.py | wc -l
  181

[1]: http://docs.python.org/3/library/os.html#os.sep