WIP Raft network base
Comments
More work
More work
Rejigger the event loop again
WIP more work
More sanity checking and cleanup
Comment log lines
Use uv_ip4_addr
WIP hand-rolled parsing, read side
Some TODOs
Raft message sending working
Duplex connections
Leader election appears to work
Clean up and dedup message writing
Fewer TODOs
Minor fixes and cleanup
Nuke c-capnproto
s/raft/sist/
Merge branch 'fucking-raft'

As of this commit, connection maintenance and leader election in
multi-instance raft mode are working. We don't sync events yet. We
also pick an inopportune time to boot -- since our boot process is
synchronous and generally takes longer than 300ms, the first thing
we do after becoming leader is go unavailable, causing a new leader
to be picked.

In other words, raft multi-instance mode isn't there yet. But
single-instance mode should be unaffected by any of this.