=act cleanup state parameters in TcpOutgoingConnection

Backport of https://github.com/spray/spray/commit/c480208f5665842103ea6fc8a1b811af38d4a667
Merge pull request #1848 from jrudolph/w/tcp-outgoing-refactoring

=act cleanup state parameters in TcpOutgoingConnection
Merge remote-tracking branch: upstream/master