Switch docs to MKDocs (#602)

Fixes #601. Merged in 6f87b32 from the md3 branch and did a lot of cleanup.

Changes include:

* Removed old docs build tool, templates, etc.

* Added MkDocs config file, etc.

* filename.txt => filename.md

* pythonhost.org/Markdown => Python-Markdown.github.io

* Markdown lint and other cleanup.

* Automate pages deployment in makefile with `mkdocs gh-deploy`

    Assumes a git remote is set up named "pages". Do

        git remote add pages https://github.com/Python-Markdown/Python-Markdown.github.io.git

    ... before running `make deploy` the first time.

1 files changed, 0 insertions, 73 deletions

diff --git a/docs/extensions/sane_lists.txt b/docs/extensions/sane_lists.txt
deleted file mode 100644
index 8f713d0..0000000
--- a/docs/extensions/sane_lists.txt
+++ /dev/null
@@ -1,73 +0,0 @@
-title:      Sane Lists Extension
-prev_title: New Line to Break Extension
-prev_url:   nl2br.html
-next_title: SmartyPants Extension
-next_url:   smarty.html
-
-Sane Lists
-==========
-
-Summary
--------
-
-The Sane Lists extension alters the behavior of the Markdown List syntax
-to be less surprising.
-
-This extension is included in the standard Markdown library.
-
-Syntax
-------
-
-Sane Lists do not allow the mixing of list types. In other words, an ordered
-list will not continue when an unordered list item is encountered and
-vice versa. For example:
-
-    1. Ordered item 1
-    2. Ordered item 2
-
-    * Unordered item 1
-    * Unordered item 2
-
-will result in the following output:
-
-    <ol>
-      <li>Ordered item 1</li>
-      <li>Ordered item 2</li>
-    </ol>
-
-    <ul>
-      <li>Unordered item 1</li>
-      <li>Unordered item 2</li>
-    </ul>
-
-Whereas the default Markdown behavior would be to generate an unordered list.
-
-Note that, unlike the default Markdown behavior, if a blank line is not
-included between list items, the different list type is ignored completely. 
-This corresponds to the behavior of paragraphs. For example:
-
-    A Paragraph.
-    * Not a list item.
-
-    1. Ordered list item.
-    * Not a separate list item.
-
-With this extension the above will result in the following output:
-
-    <p>A Paragraph.
-    * Not a list item.</p>
-
-    <ol>
-      <li>Ordered list item.
-      * Not a separate list item.</li>
-    </ol>
-
-In all other ways, Sane Lists should behave as normal Markdown lists.
-
-Usage
------
-
-See [Extensions](index.html) for general extension usage, specify `markdown.extensions.sane_lists`
-as the name of the extension.
-
-This extension does not accept any special configuration options.