add link to release notes
Refactor URL rewriting

Use a Markdown extension to hook into the build process and modify the
HTML document tree rather than using regular expressions to process
the HTML.

Fixes #240
Merge pull request #249 from fedelibre/readme-releases

add link to release notes
Move the markdown extension
Add a test case specific to #240
Add a docstring to explain the relative path Markdown extension
Correct a variable name in the tests
Merge pull request #250 from d0ugal/script

Refactor URL rewriting
Added generation of searchindex for pages
Added generation for sections h1 and h2

Did not give any decent search results without index on section level.
Documentation
Added generation of searchindex for pages
Fix PEP8 formatting issues.
Simplify the compat module
Initial draft of working Tipuesearch
Don't trim off characters - not sure when this ever made sense.
Add search to the ReadTheDocs theme
Use a modal for search on the MkDocs theme
Build out two key themes
Always clean up, even on errors