v0.3.1

Fixes push treating a mistyped page title as "nothing to push".

Fixed

• push reports titles that aren't tracked. Given a title that isn't in
  the working tree, for example a typo, push used to skip it silently, print
  "no local changes to push" and exit 0, so the edit was never published and
  nothing said so. It now names the title and exits 1:

  push: "Main Pgae" is not tracked (run 'wikisync pull' first)
  

  This applies in a preview or with --apply, alongside other pages, and in an
  empty folder. (#24, #36)