[core.cache] add 'max_size' argument to DogpileDiskCacheRegion.__init__()
add documentation
[core.interfaces] do not copy class docstring
[core.interfaces] remove whitelist feature from lock()

which has not been used so far. It is probably bad
style to use it anyhow.
[core.interfaces] set _locked directly in ImmutableMeta.__call__()

which prevents two unneccesary function calls.
[core.interfaces] performance tweak

According to %timeit, key.startswith('_') is about three times
slower than key[0] == '_'.
[core.interfaces] use self.init_arguments in with_arguments() and with_()
[core.interfaces] move generate_sid decorator to the playground

It is used nowhere and no one has ever tested it.
[demos] give cg-oned a valid python module name
[docs] switch from numpydoc to sphinxcontrib-napoleon which actually works

sphinxcontrib-napoleon seems to have less features, we will have to
reevaluate the situaion.
[install] remove 'nose' from setup_requires
[docs] add 'index' contents.rst

eliminating a warning generated by sphinx
[docs] monkey apidoc to prevent generation of documentation for Cython modules
[docs] for now do not include inherited members

until we have a decent way to do so
[docs] add documentation
[docs] fix reST syntax errors
[docs] monkey sphinx to correctly handle our cache decorator