Fix #978: intersphinx_mapping also allows a list as a parameter

CHANGES

@@ -12,6 +12,7 @@ Features added
 * #3241: emit latex warning if buggy titlesec (ref #3210)
 * #3194: Refer the $MAKE environment variable to determine ``make`` command
 * Emit warning for nested numbered toctrees (refs: #3142)
+* #978: `intersphinx_mapping` also allows a list as a parameter
 
 Bugs fixed
 ----------

sphinx/ext/intersphinx.py

@@ -242,7 +242,7 @@ def load_mappings(app):
     cache = env.intersphinx_cache
     update = False
     for key, value in iteritems(app.config.intersphinx_mapping):
-        if isinstance(value, tuple):
+        if isinstance(value, (list, tuple)):
             # new format
             name, (uri, inv) = key, value
             if not isinstance(name, string_types):