Set nested_sections to False for Sphinx-Gallery 0.11.0 regarding a correct navgation bar (#2046)

Author: yvonnefroehlich

doc/conf.py

@@ -116,6 +116,10 @@
     "image_scrapers": (PyGMTScraper(),),
     # Removes configuration comments from scripts
     "remove_config_comments": True,
+    # Disable "nested_sections" (default is True), to
+    # generate only a single index file for the whole gallery.
+    # This is a new feature up on Sphinx-Gallery 0.11.0.
+    "nested_sections": False,
 }
 
 # Sphinx project configuration