mrb_sys_fail raises SystemCallError if we have it.
Merge branch 'master' into pr-systemcallerror
Merge branch 'master' into pr-systemcallerror
mrb_str_new2 -> mrb_str_new_cstr
Merge pull request #996 from iij/pr-systemcallerror

mrb_sys_fail raises an instance of (subclass of) SystemCallError if we have it