rebase: prioritize indicating an interrupted rebase over update (issue5838) This should also cover the transplant extension, and any other non clearable states.

tests: demonstrate inconsistent messaging around interrupted rebases

tests: adapt test-check-pylint to run on Windows The line endings are explicitly converted because this was ending up with '\r (no-eol) (esc)' lines, in addition to the usual '\r (esc)' lines. I've seen the fakerc output on other recently installed systems though (10.13 and/or Fedora 26). Unfortunately, the output here uses '\\' on Windows, so glob away the whole path.

hghave: avoid a deadlock reading the child process's output The output of `pylint` is voluminous enough that it fills the buffer on Windows, and waited for the parent to read it out. But the parent was waiting on the child to exit. I'm not sure what the intent of setting `ret = -1` in the exception handler just above this was...