Merge #1859

1859: Update links to documentation r=rehandalal a=mythmon

I set up a redirect for most of the docs from RTD to gh-pages, and made the root of the RTD page contain a message that the docs have moved. I think we can update our links now.

Co-authored-by: Michael Cooper <mythmon@gmail.com>

README.md

@@ -18,4 +18,4 @@ MaxMind, available from https://www.maxmind.com.
 
 Please see the [Developer Setup] documentation to get started.
 
-[Developer Setup]: https://normandy.readthedocs.io/dev/install.html
+[Developer Setup]: https://mozilla.github.io/normandy/dev/install.html

normandy/recipes/api/v3/serializers.py

@@ -177,7 +177,7 @@ def validate_extra_filter_expression(self, value):
             jexl = JEXL()
 
             # Add mock transforms for validation. See
-            # http://normandy.readthedocs.io/en/latest/user/filter_expressions.html#transforms
+            # https://mozilla.github.io/normandy/user/filters.html#transforms
             # for a list of what transforms we expect to be available.
             jexl.add_transform("date", lambda x: x)
             jexl.add_transform("stableSample", lambda x: x)