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.
Add id to glossary entry

This is needed to enable users jump to glossary entries.
use pandocfilters.stringify
Updating files to move  into root directory
Merge branch 'gh-pages' into moving-source-to-root-directory
Add id4glossary.py into Makefile
Store Pandoc's filter at tools/filters
Merge pull request #44 from r-gaia-cs/add-anchor-in-glossary

Add id to glossary entry
Clearing up status of notebooks and R Markdown files
Bringing in changes to add IDs to glossary entries
Merge pull request #45 from gvwilson/moving-source-to-root-directory

Updating files to move  into root directory
fill in missing '$ ' in prompt
Update validator for changes in directory structure
Merge pull request #50 from abought/validator

Update validator for changes in directory structure
Merge pull request #18 from r-gaia-cs/add-script-for-label

Add small script to setup label in lesson repo
Merging CSS