major redesign, reprising connection as DuplexConnection (#102)

* major redesign, reprising connection as DuplexConnection, greatly simplifying the I/O loop

* cargo fmt

* clean up

* SND less often

* high_bandwidth

* clean up

* remove SyncLossyConn

* fix formatting

* !ensure_open => should_close

* clarify SND exit, also ensure we only do step 5 (n16 send) when sending a new packet

* reduce timestamp_rollover stream duration to 2 hours

* remove DropPackets, will adress with seperate PR

* clean up and comment connection close

* fix up DuplexConnection unit tests

* cargo fmt

* fix not_enough_latency test and fix 32-bit testcases failing

* fix commenting of high_bandwidth

* fix clippy error

* fix not_enough_latency test

* fix rendezvous test

* revert change to number of tests done

* Push empty commit for CI

* Check off congestion control

* re-disable high_bandwidth

Co-authored-by: Russell Greene <russellgreene8@gmail.com>

README.md

@@ -24,7 +24,7 @@ Reference implementation is available at https://github.com/haivision/srt
 - [x] Special SRT packets (partial)
 - [x] Actual SRT (TSBPD)
 - [x] Timestamp drift recovery (not throughly tested)
-- [ ] Congestion control
+- [x] Congestion control
 - [x] Encryption
 - [x] Bidirectional