The emission of an event was being logged twice, and the second time was
logging the pickled content of the event. This pickled content contained line
breaks and other things that caused strange output on the client log.

This commit removes the second loggin of the event pickled content.

Closes #7130.

previous regex wasn't capturing addresses of type ipc://<path>

Closes: #7089

Tag leap.common version 0.4.0

As @meskio pointed out, some cases could need a dedicated pool with
different parameters.
This is a suggested implementation where the pool is reused by default,
creating a dedicated one just if needed/asked. This way we ensure that
resources are under control and special cases are still handled.

Before this commit, protobuf and protobuf.socketrpc were used to serialize and
transmit messages between events clients. This change implements a simpler ZMQ
client/server events mechanism that uses ZMQ sockets for transmitting messages
from clients to server and to redistribute such messages to subscribed
clients.

Closes: #6359

Implements an HTTP client the twisted way, with a focus on pinning the
SSL certs.

* Related: #6506

The certificate validity times were converted to local time and later on
compared with UTC time, which caused the certificate not being updated
at the right times.
Add tests to be sure this is not happenning again.
Add a joint pem file for the existing cert and key files to ease test.

- Resolves: #6994