Save follower count and note count in user.

lib/pleroma/user.ex

lib/pleroma/web/ostatus/handlers/note_handler.ex

lib/pleroma/web/twitter_api/twitter_api.ex

test/support/factory.ex

test/user_test.exs

test/web/ostatus/ostatus_test.exs

test/web/twitter_api/twitter_api_test.exs

test/web/twitter_api/views/user_view_test.exs