Splice in project template

I tried to merge it so that future updates from the template will be
much easier.

The template is hosted at:
https://github.com/ethereum/ethereum-python-project-template

mypy.ini

@@ -1,16 +1,20 @@
 [mypy]
-warn_unused_ignores = True
-ignore_missing_imports = True
-strict_optional = False
+
 check_untyped_defs = True
 disallow_incomplete_defs = True
 disallow_untyped_defs = True
 disallow_any_generics = True
 disallow_untyped_calls = True
+disallow_untyped_decorators = True
+disallow_subclassing_any = True
+ignore_missing_imports = True
+strict_optional = False
+warn_unused_ignores = True
+strict_equality = True
 warn_redundant_casts = True
+warn_return_any = True
 warn_unused_configs = True
 warn_unreachable = True
-strict_equality = True
 
 [mypy-libp2p.kademlia.*]
 ignore_errors = True