This commit marks (hopefully) ever one-parameter constructor as explicit.
It also uses override in (hopefully) all circumstances where a virtual
method is overridden.
There are a very few other minor changes - most of them were necessary
to get everything to compile (like one additional constructor). In one
case I changed an implicit operation to an explicit string conversion -
I think the automatically chosen conversion was much more convoluted.
This took longer than I want to admit but not as long as I feared :)
* origin/topic/jsiwek/improve_comm_loop:
Add a simple FD_Set wrapper/helper class.
Fix Pipe copy/assignment to make a copy of flags.
Fix possible abort on writing to a full pipe.
Remove timeouts from remote communication loop.
