Fixed the jQuery not loaded issue on RTD page

Author: JohanMabille

docs/source/conf.py

@@ -18,7 +18,7 @@
 def setup(app):
     app.add_css_file("main_stylesheet.css")
 
-extensions = ['breathe']
+extensions = ['breathe', 'sphinx_rtd_theme']
 breathe_projects = { 'xtensor-python': '../xml' }
 templates_path = ['_templates']
 html_static_path = ['_static']