BUFR input samples

These are intended to be inputs to a decoder regression test. Ideally,
they should be reasonably short (to test for specific conditions and not
bloat the package), have some indication as to purpose (a comment at the
beginning, for example), and only use BUFR elements from the default tables
(../../Tables/).

Broken (non-decodable) examples are also welcome. A decoder should be
able to survive bad data.
