- Breaks tests in dependent repos like soledad otherwise,
  because server.key could not be found

to make simpler the import of the tx client

- Related: #7274

In case the http client loses connection, it has to clear
it's timeout or the reactor will be left in a dirty state
Fixing this solves a problem with some of the tests in Soledad
that were trying to run on a dirty reactor

Since register and unregister cant be used without full zmq initialization,
it should make sense to also check flag for them.

Checking was done inside of emit method. Doing on emit function at
a module level makes it cleaner with less lines inside of check.

Test client will only start with flag set to True.
Change EventsGenericClientTestCase to set the flag on the
first line of setUp.

Change EventsClientThread behavior so it won't start anymore if
the events flag is set to False