[parrot/parrot] e1b3af: [pmc] Add Coroutine.reset() method

[GitHub]

  Branch: refs/heads/rurban/coro-reset-gh564
  Home:   https://github.com/parrot/parrot
  Commit: e1b3aff878e473177312439b0edbe50e94915574
      https://github.com/parrot/parrot/commit/e1b3aff878e473177312439b0edbe50e94915574
  Author: Reini Urban <rurban at cpanel.net>
  Date:   2014-10-06 (Mon, 06 Oct 2014)

  Changed paths:
    M docs/pmc/subs.pod
    M src/pmc/coroutine.pmc
    M t/pmc/coroutine.t

  Log Message:
  -----------
  [pmc] Add Coroutine.reset() method

Mentioned in GH #564.

It is however more efficient to clone an initial coro and
copy this saved clone back, as the context does not need to
be recreated afresh.