This means that:
* if one subcommand implementation is buggy, other subcommands are still tested and
have a chance to pass
* we can exclude known-buggy subcommands from the Makefile
* when a test failure happens, we get much shorter logs (only logs for
that subcommand's I/O)
* Remove some 'Ergo' marks
These are not ergo-specific specs
* Make chathistory test less Ergo-specific
Although they can only run on Ergo for now, as Unreal has a couple
of minor bugs that prevents them from passing.
* Fix synchronization issue
(NickServ sets MODE +r, which is unexpected caught by the next
self.assertMessageMatch call)