Improve muxer test coverage. Fix several muxer issues

[Nashatyrev]

• More muxer tests
  • Refactor MuxHandlerAbstractTest: add ability to handle outbound messages
  • Control and check ByteBuf allocations and releases
  • Add more testcases and assertions
• Fix found issues:
  • [Generic] (buffer leak) release message buffer if inbound frame have non-existing streamId: https://github.com/libp2p/jvm-libp2p/pull/285/commits/71c68c45cacd8760c5e4547138fe59463ceb0ef7
  • [Yamux] Process RST (Reset) flag: https://github.com/libp2p/jvm-libp2p/pull/285/commits/42e40f656050e72904b6eb4b7aa154550d0477b7
  • [Generic] Writing to a stream which was prior closed should be prohibited: https://github.com/libp2p/jvm-libp2p/pull/285/commits/d3c458075933a01bc601504caf45b1a1ee0fd1c4
  • [Generic] Receiving a data on a steam which was remotely closed should result in exception (recoverable, i.e. connection should not be terminated): https://github.com/libp2p/jvm-libp2p/pull/285/commits/8974317dfdb1825bde057a4fe99a8e4518a740fb
  • [Yamux] switch the logic of onLocalDisconnect() and onLocalClose() methods. onLocalDisconnect() should leave the stream open for inbound data: https://github.com/libp2p/jvm-libp2p/pull/285/commits/820c252d81de205bc3adf3f682d05064aed4cb8a
  • [Yamux] need to clean up stream entries on any kind of stream closure (local Reset, remote Reset, local + remote Close): https://github.com/libp2p/jvm-libp2p/pull/285/commits/66ef36ba7ef5a61b0dc2455a12bf92eb1501e13d
• Convert RemoteWriteClosed to singleton

Part of #272 Follow up to #281 Fix #27