[c-lightning] c-lightning 0.6.1 release, aka "Principled Opposition to SegWit"

[Rusty Russell]

We're pleased to announce c-lightning 0.6.1, named by co-maintainer ZmnSCPxj.

Highlights for c-lightning users

 * Less stuck payments: Liveness ping test before locking up funds with peers.
 * Better routing: now considers size of channels.
 * Fewer spurious closes: fee estimate improvements, and new feerates command
 * Several annoying bugs fixed.
 * Ubuntu PPA at https://launchpad.net/~lightningnetwork/+archive/ubuntu/ppa

Highlights for the network:

 * Gossipd now less spammy with channel_update.
 * option_data_loss_protect to protect peers against being out-of-date.
 * Payment errors now refer to the correct channel.

Internal Improvements

 * Simplified client flow; after init message exchange by connectd, each
   is isolated in its own daemon.
 * JSON parameter handling vastly simplfied.
 * Python testing framework now uses proper fixtures, and split into
   separate files.
 * Many other cleanups and clarifications.
 * We keepachangelog.com!

The details can be found in the CHANGELOG:
        https://github.com/ElementsProject/lightning/blob/v0.6.1/CHANGELOG.md

Contributions:

We're grateful for all the bug reports and suggestions and your patience as we sometimes struggled to address them: please keep them coming!

Since 0.6 we've had 517 commits from 31 different authors, 15 of whom
were first-time c-lightning contributors:

Bertrand Marlier
Cryptcoin Junkey
Fabian Raetz
Hiroki Gondo
Jonathan Zernik
Jordan Baczuk
Ronald Mannak
Simon Vrouwe
Stephanie Stroka
gallizoltan
lisa neigut
lucash-dev
mikhaelsantos
tock203
wintercooled

Cheers,
Rusty, Christian and ZmnSCPxj.