Support lambdas in module commands
Enable UBSan in travis
Merge branch 'lambda'
Revise CChan::JoinUser() & AttachUser()

The old AttachUser() that sent JOIN without topic or names replies
would leave clients in incomplete/broken state. JoinUser() was doing
two things; depending on passed arguments it was either joining user
on the channel on IRC, or attaching clients (properly). Now JoinUser()
joins the user on IRC, and AttachUser() attaches as expected from the
method names.
ListClients: add identifier column
Update Csocket to b5185dc

> Fix IsConnected() to return false when Disconnected() gets called
Replace CIRCNetwork::FindClient() with FindClients()

FindClient() is not enough, because there are no restrictions to used
identifiers. They don't necessarily need to be unique, and the same
identified client might re-connect meanwhile a ghost connection is
still hanging there.
Merge pull request #752 from jpnurmi/findclients

Replace CIRCNetwork::FindClient() with FindClients()
Merge pull request #751 from jpnurmi/csocket

Update Csocket to b5185dc
Merge pull request #753 from jpnurmi/listclients

ListClients: add identifier column
znc-buildmod: build output to the current working directory

If I run znc-buildmod in ~/.znc/modules and pass it a module source
from another directory, I expect the build output to go to the current
working directory instead of the source directory of the module.
Fix build without threads
Fix #759 - channels cannot be reattached

This was a regression caused by aed1d61 :(
Update Csocket to 5746796ca55d21fa185caf7c58d015f650b77768
Honor SSL ciphers in ZNC->Server connections
Merge pull request #758 from jpnurmi/buildmod

znc-buildmod: build output to the current working directory
Pass timestamp to playline hooks

This allows implementing timestamp-based (eg. client specific - #343)
filtering of playback buffers. For clients that don't support server-time,
getting an accurate timestamp out of a raw buffer playline is impossible.
Merge pull request #760 from jpnurmi/attach

Fix #759 - channels cannot be reattached
Merge pull request #756 from jpnurmi/timestamp

Pass timestamp to playline hooks
Validate TLS certificate of IRC server.

Fix #156