Add Google Colab launch button support (#148)

* Add Google Colab launch button support

* Update repository URLs from jstac to QuantEcon and add nb_repository_url

* Fix nb_repository_url to point to .notebooks repository

Author: mmcky

lectures/_config.yml

@@ -10,15 +10,17 @@ sphinx:
     html_theme_options:
       header_organisation_url: https://quantecon.org
       header_organisation: QuantEcon
-      repository_url: https://github.com/jstac/continuous_time_mcs
-      # nb_repository_url: https://github.com/QuantEcon/lecture-python.notebooks
+      repository_url: https://github.com/QuantEcon/continuous_time_mcs
+      nb_repository_url: https://github.com/QuantEcon/continuous_time_mcs.notebooks
       twitter: quantecon
       twitter_logo_url: https://assets.quantecon.org/img/qe-twitter-logo.png
       og_logo_url: https://assets.quantecon.org/img/qe-og-logo.png
       description: These lectures provides a short introduction to continuous time Markov chains designed and written by Thomas J. Sargent and John Stachurski.
       keywords: Python, QuantEcon, Quantitative Economics, Economics, John Stachurski, Schmidt Futures, Markov Chains
       analytics:
         google_analytics_id: G-MVZ2FSB14W
+      launch_buttons:
+        colab_url: https://colab.research.google.com
     bibtex_reference_style: author_year
     mathjax3_config:
       tex: