add django-email-confirm-la, twostram submodules

add missing django-email-confirm-la dependencies
fix model manager override function name (old name is deprecated)
remove REQUIRED_FIELDS from our custom user model because they create required command line arguments with the createsuperuser management command
bump ext/twostream
remove 3rd party as a filter and change party to an enum throughout
alert the user if the pledge is not yet confirmed
we can show pledge defaults even for anonymous users
create actor/recipient instances