v0.3.0

What's changed?

- Updated getopt_long_only(3) API: it's now stateful, which means usage
  can generate as expected (with a single dash).

  This means that parseArgc:argv:longOnly:error is out and longOnly
  (getter = isLongOnly) is in. It also means a fancy new initializer:
  +[BRLOptionParser longOnlyParser].

- Error messaging bug fix for getopt_long_only(3).

Signed-off-by: Stephen Celis <stephen@stephencelis.com>