Consistently use snake_case for filenames

Replicates graphql/graphql-relay-js@24a6d33

Author: Cito

src/graphql_relay/__init__.py

@@ -18,7 +18,7 @@
 )
 
 # Helpers for creating connections from arrays
-from .connection.arrayconnection import (
+from .connection.array_connection import (
     connection_from_array,
     connection_from_array_slice,
     cursor_for_object_in_connection,
@@ -41,7 +41,7 @@
 
 # Deprecated functions from older graphql-relay-py versions
 # noinspection PyProtectedMember,PyUnresolvedReferences,PyDeprecation
-from .connection.arrayconnection import (  # noqa: F401
+from .connection.array_connection import (  # noqa: F401
     connection_from_list,
     connection_from_list_slice,
 )

…phql_relay/connection/arrayconnection.py …hql_relay/connection/array_connection.pysrc/graphql_relay/connection/arrayconnection.py renamed to src/graphql_relay/connection/array_connection.py src/graphql_relay/connection/arrayconnection.py renamed to src/graphql_relay/connection/array_connection.py

@@ -9,7 +9,7 @@
 )
 
 from graphql_relay.node.node import node_definitions, global_id_field, from_global_id
-from graphql_relay.connection.arrayconnection import connection_from_array
+from graphql_relay.connection.array_connection import connection_from_array
 from graphql_relay.connection.connection import connection_args, connection_definitions
 from graphql_relay.mutation.mutation import mutation_with_client_mutation_id