Avoid warnings
tamer/autoconf.h is no longer auto generated.

Since it contains no configuration variables (intentionally).
Don't die if a tamer::fd is closed after the driver's destroyed.

c1d7d90e actually did nothing.
Use explicit tamer::make_event calls.

In preference to constructors.
Internal: Rename simple_event members of event.
Internal: Clean up relationships among make_event, event ctors, and rvous.

200 lines fewer code, more sense.