Blockquote margins
Add small script to setup label in lesson repo

The script make easy to create the labels and keep it compatible
across repositories.
Improve script to setup labels

Address @gvwilson comments:

- add an example
- variables in the shell are UPPER_CASED
- Check that repository exists using a HEAD
Avoid JSON outup from setup-labels

As requested by @gvwilson, don't print the JSON response from
GitHub.

Others changes:

- Use arrays to store the label and its color
- Print message if fail
Improve callout box

and "learning objectives" box.
Fix template layout

The body variable at Pandoc template **must** not be indented
because the indentation will propagate into the HTML.

Example:

    $ cat page.html
    <!DOCTYPE html>
    <html>
      <body>
        $body$
      </body>
    </html>
    $ pandoc -s -t html --template=page -o sample.html sample.md
    $ cat sample.html
    <!DOCTYPE html>
    <html>
      <body>
        <pre><code>def foo():
            return None</code></pre>
      </body>
    </html>

Solution:

    $ cat fix.html
    <!DOCTYPE html>
    <html>
      <body>
    $body$
      </body>
    </html>
    $ pandoc -s -t html --template=fix -o sample-fix.html sample.md
    $ cat sample-fix.html
    <!DOCTYPE html>
    <html>
      <body>
    <pre><code>def foo():
        return None</code></pre>
      </body>
    </html>
Breaking instructions into pieces and explaining labels
Putting link to layout instructions in the first paragraph
Changing names based on feedback from @willingc
Merge pull request #30 from r-gaia-cs/fix-code-indetation

Fix template layout
making python script runnable for pandoc
added shebang to the python pandoc script
Merge pull request #36 from twitwi/make-python-script-runnable-for-pandoc

making python script runnable for pandoc
remove .prereq from readme
trigger prereqs class with title

Previously, Div creation was triggered by a Blockquote that began with a
header that contained a single class that was in a list of special
classes.

Now, Div creation is *also* triggered by a Blockquote that begins with a
header that has it's text contained in a list of special titles. The
title is used to lookup an appropriate class to give the Div.

In particular, 'prerequesites' is a special title, giving the class
'prereq'.

This input:

    > ## Prerequesites
    >
    > A short paragraph describing what learners need to know before
    > tackling this lesson.

will trigger this output:

    <div id="prerequisites" class="prereq">
    <h2>Prerequisites</h2>
    <p>A short paragraph describing what learners need to know before
    tackling this lesson.</p>
    </div>
Small improve at tools/blockquote2div.py

- Use UPPERCASE for global constants
- Add Learning Objectives to SPECIAL_TITLES
- Fix samples
clarify documentation, make all classes special

This means that you can trigger div creation by

1. Using a special title
2. Using a special class on an arbitrary title
Merge pull request #37 from aaren/prereq-divs

Prereq divs
Merging with gh-pages
Merge pull request #31 from gvwilson/splitting-lesson-instructions

Splitting lesson instructions