Release v0.0.26

Changelog:

• Both stream multiplexers now coalesce small writes to reduce secio/tls overhead and reduce the number of packets sent. This introduces a 100us delay when writing a small amount of data to an otherwise idle connection but this shouldn't be noticeable on a real network.
• Yamux now correctly implements deadlines so SetDeadline on a yamux stream will now affect an active read/write.
• The connection manager now trims connections in a background worker instead of trimming every time we receive a new connection. This should make it more reliable. See libp2p/go-libp2p-connmgr#42.
• The connection manager now uses segmented locking to reduce lock contention when using the UpsertTag function to atomically update tags.
• Update go-smux-{multistream,multiplex,yamux} to import them into go mod. If you get errors about missing dependencies/tags, please update everything.