Fix close/settle event external_state usages
Fix close/settle event external_state usages

There were a couple of api-misuses that prevented closing a channel
from properly updating the channel.external_state.

charles-cooper/raiden,tomaaron/raiden,tomashaber/raiden,tomaaron/raiden,tomaaron/raiden,charles-cooper/raiden,tomashaber/raiden,hackaugusto/raiden,tomashaber/raiden,tomashaber/raiden,hackaugusto/raiden,tomashaber/raiden,tomaaron/raiden