[parrot/parrot] ac13b0: [cage] even more const io api arguments

[GitHub]

  Branch: refs/heads/smoke-me/stringbuilder-gh1123
  Home:   https://github.com/parrot/parrot
  Commit: ac13b03e39396ae34aee5ac3aa73fd78debdbe7e
      https://github.com/parrot/parrot/commit/ac13b03e39396ae34aee5ac3aa73fd78debdbe7e
  Author: Reini Urban <rurban at cpanel.net>
  Date:   2015-02-01 (Sun, 01 Feb 2015)

  Changed paths:
    M include/parrot/io.h
    M src/io/api.c
    M src/pmc/filehandle.pmc

  Log Message:
  -----------
  [cage] even more const io api arguments