do not use deprecated compiler module

At least in Python versions >= 2.6, fixes #115
make nose.util.isgenerator() work on Python 3

- True if either a generator expr or a generator function
- isgenerator() to use existing UnboundMethod workaround
Fix spelling option names in docstring

The cover-package option and environment variable name in the docstring
are spelled with a plural, whereas the actual names are not. Trying to
use the plural version results in a `nose.config.ConfigError`.
replace 'pep08' with 'PEP 8'
Use sphinx PEP reference
fix case sensitivity in _samefile

_samefile should be case-insensitive on case-insensitive file systems
(e.g. Windows). This way sameModule will not re-import and overwrite
modules that are already imported.
This fixes #19
test errors against BaseException in capture.py

addCaptureToErr in capture.py is formatting exceptions that inherit from
Exception but some exceptions inherit from BaseException (e.g.
SystemExit).
In any case, addCaptureToErr should not fail if the exception was not
formatted so ev must be ensured to be a string.
This fixes #612
getpackage in util.py should only parse files and packages

Directories that end with .py but are not Python packages should not be
parsed as if they are modules.
getpackage now verifies that the path is either a .py file or a package.
This fixes #526
Merge pull request #651 from zr40/patch-1

replace 'pep08' with 'PEP 8'
Merge pull request #650 from bwbaugh/cover-docstring

Fix spelling option names in docstring
Fix include directive in autoplugin_directive.

It appears that the include directive does not like absolute paths, and
ends up stripping the leading '/'.  This means that it fails to find the
python module, and warns in the Sphinx build.

Instead of using an absolute path, let's formulate a relative path using
docutils.utils.relative_path().  Since the path needs to be relative to
the document, let's pull that from state_machine.document['source'].
Merge pull request #648 from kimscheibel/master

Do not use deprecated compiler module.
Fix docs describing the arguments of formatFailure and formatError

- emphasize that the error tuple has to be returned even if it is not
  modified.
- remove highly misleading note about returning the test arg.
Merge pull request #492 from abeld/formatFailure-doc-fixes

Fix docs describing the arguments of formatFailure and formatError
Fix line in nosetests.1 being treated as man directive

This is actually a bug in Docutils, but here we work it around
until it is properly fixed.
Use Sphinx manpage writer instead of Docutils one

And update Makefile accordingly.
Remove docinfo from man.rst, not needed with Sphinx builder
Regenerate the man page
Merge pull request #642 from mitya57/manpage-formatting

Add manpage building support to conf.py, and fix formatting errors
Remove manpage and manbuilder in favor of Sphinx's man page builder.