* cygthread.cc (cygthread::detach): Revert to just waiting for thred event

* cygthread.cc (cygthread::detach): Revert to just waiting for thred event
since waiting for anything else is racy.
* timer.cc (timer_tracker::hcancel): Rename from cancel.
(timer_tracker::cancel): New method.
(timer_tracker::th): Remove.
(timer_tracker::~timer_tracker): Call cancel method.
(timer_tracker::timer_tracker): Ditto.
(timer_tracker::timer_tracker): Always, clear cancel, even though it is
probably not strictly necessary for ttstart.
(timer_thread): Accommodate cancel -> hcancel rename.
(timer_tracker::settime): Ditto.
(timer_tracker::gettime): Ditto.
(timer_delete): Ditto.
* cygwin.din: Export _ctype_.
* include/ctype.h: Mark that _ctype_ is imported.