Merge pull request #19 from luisincrespo/master

Use context option (if provided)

Author: syrusakbary

Diff for: flask_graphql/graphqlview.py

@@ -48,7 +48,7 @@ def get_root_value(self, request):
         return self.root_value
 
     def get_context(self, request):
-        return request
+        return self.context or request
 
     def get_middleware(self, request):
         return self.middleware