Making everything consistent is a bit awkward, since this is a
commonly used attribute, but I've done my best.
Reasons for not consolidating on `filename`:
* It is often used for the "basename" (last component in the path).
Using `source_path` makes it clear that this attribute can contain
multiple components.
Reasons for not consolidating on `filepath`:
* It is barely used in the Pelican source, and therefore easy to
change.
* `path` is more Pythonic. The only place `filepath` ever show up in
the documentation for `os`, `os.path`, and `shutil` is in the
`os.path.relpath` documentation [1].
Reasons for not consolidating on `path`:
* The Page elements have both a source (this attribute) and a
destination (.save_as). To avoid confusion for developers not aware
of this, make it painfully obvious that this attribute is for the
source. Explicit is better than implicit ;).
Where I was touching the line, I also updated the string formatting in
StaticGenerator.generate_output to use the forward compatible
'{}'.format() syntax.
[1]: http://docs.python.org/2/library/os.path.html#os.path.relpath
If the destination directory specified by FILES_TO_COPY does not
exist, site generation crashes with a CRITICAL error. This creates the
destination if it does not exist.
Used an exception so show error state.
Used a bool flag to make sure the error is only shown once PER error.
Updated tests to check for the correct Exception raised
Added Debug level logging for each deletion
Added error level logging when a delete has an exception
Built a test case for clean_output_directory in tests.utils.py
Updated `settings` in documentation to reflect new behavior
Removed the tip from the bottom of getting started since this setting should no longer break web servers pointing to the output directory.
As it is done when reading the file, we need to remove html tags for the
permalink and the slug (this is done here for the notmyidea and simple themes).
While modifying the themes I also replaced the `pagename` template tag with
`article.url` (`pagename` was an empty variable, no more used ?).
