Add Nethernet support (netty-transport-nethernet) (#4)

* Add transport-nethernet package

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* Correct discovery packet length and properly encode discovery string length as varint

Co-authored-by: RaphiMC <50594595+RaphiMC@users.noreply.github.com>
Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* Refactor NetherNetClientChannel using RTCDataChannelObserver to succeed connectPromise

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* Encourage use of single PeerConnectionFactory

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* Switch to data only webrtc lib

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* Refactor to support joining realms

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* Fix issues with connectionId being signed in SDP strings; fix LAN server channel

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* Expose ice servers in NetherNetXboxSignaling

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* Remove native depends

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* More robust logging and ICE/TURN parsing

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* Properly track NetherNetServerChannel state

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* Prep for nethernet release

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* Fix option access

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* Add max retries for client connect

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* Fail connect promise if target network id is not found

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* Add case for Delivery Acknowledgement

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* Refactor to use specific functional interfaces for all string handlers; javadoc formatting

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* Use connectexception if we can't reach xbox signaling

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* Complete with ConnectException if we cannot connect to xbox signaling wss; ensure signaling handler is removed on close

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* Use ConnectException for handshake failure

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* Update README structure

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

* Small README tweaks

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

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Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>
Co-authored-by: RaphiMC <50594595+RaphiMC@users.noreply.github.com>