Update matterircd to 0.16.5.

0.16.5
------
New features
- Add support for private channels in slack #142

Bugfix
- Slack: fixes join/parts #143, #146
- Slack: fixes away #144

0.16.4
------
Bugfix
- Fix some messages going to &messages #140

0.16.3
------
Bugfix
- Fix crash on /nick change when not logged in #141

0.16.2
------
Bugfix
- Remove crash on channel lookup of private messages

0.16.1
------
Bugfix
- Remove debug code which could cause a crash
- Only append channel name to sender once in &messages

0.16.0
------
New features
- -conf option (for a config file). See
  https://github.com/42wim/matterircd/blob/master/matterircd.toml.example for
  an example. Thanks @slowbro for this PR.

New config file options

JoinExclude: an array of channels that won't be joined on IRC.
Messages that get sent to unjoined channels (but you're joined on mattermost)
will get sent to the &messages channel.
You can still /JOIN exclude channels.
JoinExclude = ["#town-square","#boringchannel"]

JoinInclude: an array of channels that only will be joined on IRC.
If it's empty, it means all channels get joined (except those defined in
JoinExclude).
Messages that get sent to unjoined channels (but you're joined on mattermost)
will get sent to the &messages channel.
JoinInclude = ["#devops"]

PartFake: a bool that defines if you do a /LEAVE or /PART on IRC it will also
actually leave the channel on mattermost.
Default false
PartFake = true

- don't log passwords used with 'mattermost' and 'slack'. Closes #73

Bugfix
- Already read messages are replayed again and again #130
- Update to latest mattermost (4.6) libs
- Deprecated flags -bindinterface and -port removed

0.15.0
------
New features
- Support mattermost 4.2 and higher (4.x) (use mattermost v4 API)
- Add -mmskiptlsverify option to skip TLS certificate checks on mattermost

Enhancements
- Display nickname, if set #120
- Replace IRC parsing function with shellwords like function to allow for
  passwords with spaces. (#8)


(bsiegert)