Log Message:
(pkgsrc)
 - Add following DEPENDS
   +DEPENDS+=      p5-Canary-Stability-[0-9]*:../../devel/p5-Canary-Stability
 - Drop patch-libev_ev.c (seems to be fixed)
 - Add comment on patch (from cvs log)
(upstream)
 - Update 4.18 to 4.21
-------------------
   Changes marked with (libev) are changes in libev, and have more
   documentation in the libev Changes file.
4.21 Mon Jul 13 21:47:33 CEST 2015
        - allow argument in timer->again.
        - document timer->remaining.
        - document default repeat value for timer->set.

4.20 Sat Jun 20 13:07:34 CEST 2015
        - added stability canary support.
        - truly rely on automatic configuration for clock_gettime and others.
          unfortunately, this doesn't help with activeperl and similar perls,
          which define _POSIX_TIMERS without actually implementing any of it.
        - (libev, ecb) make it compile as C++ again.
        - (libev) fix a potential aliasing issue when accessing watcher cbs.