* Rework swarm and allow interrupting a dial
* Improve the UniqueConnec situation
* Remove UniqueConnec::get
* Rename `get_or_dial()` to `dial()` and add `dial_if_empty()`
* Clean the UniqueConnec is the future is dropped
* Rename `set_until` to `tie_or_stop` and add `tie_or_passthrough`
* Add some tests, docs
* Fix memory leak with tasks registration
* Interrupt dialing when a UniqueConnec is dropped or cleared
* Add memory transport.
* Change test to be compatible with rust stable.
* Address concerns
* Add some documentation and minor fixes
* Move transport test to memory module
