Remove stevedore from dependencies

Stevedore is a cool and useful library, but I believe that most of its
features are rare in use. In order to reduce project dependencies I
implement a small extension manager as part of Dooku library [1].

[1]: https://github.com/ikalnitsky/dooku
Implementation of the blog generator

This commit adds implementation of the blog generator, which
incorporates feed, index page and tags pages generators.

Fixed #1
Merge pull request #13 from ikalnitsky/blogenerator

Implementation of the blog generator
Merge pull request #15 from ikalnitsky/drop-stevedore

Remove stevedore from dependencies
The content of holocron example post is improved

This commit changes the text of holocron.mdown file, adding info about holocron
features and its basic usage.

Fixed #16
Merge pull request #20 from ikalnitsky/example-improvements

The content of holocron example post is improved
Use Dooku from PyPI

The first public beta version of Dooku was released today (Aug 30, 2014).
Since now we should use only public versions (no dev versions anymore).
Merge pull request #23 from ikalnitsky/use-dooku-from-pypi

Use Dooku from PyPI
Fixes serving of newly added files

This commit handles the issue in serve command which cannot host
new files.

Fixed #19
Serve enhanced for tracking of theme files

This commit enhances serve, so it now tracks the files in user's and
default theme directories.

Fixed #18