Release Name: 0.53

Notes:
Syck 0.53 continues the development of the unstable
branch of Ruby's builtin YAML support.  The Ruby
extension has made big strides in the last day,
certainly worth releasing to the public.  While
there are still lots of bugs and missing pieces, most
YAML documents should load fine.


Changes:
    README.EXT: more docs.

    ext/ruby/ext/syck/rubyext.c:
    - moved Object#yaml_new into the node_import and made it the
      default behavior.
    - the target_class is always called wih yaml_new, prepended
      a parameter, which is the klass.
    - loaded nodes through GenericResolver show their style.
    - YAML::Syck::Node#transform works.
    - bug with YAML::Syck::Emitter#level

    ext/ruby/lib/yaml.rb: reworking YAML::Stream to use the new
      emitter.

    ext/ruby/lib/yaml/stream.rb: ditto.

    ext/ruby/lib/yaml/rubytypes.rb: use of new yaml_new syntax.

    ext/ruby/lib/yaml/tag.rb: the tag_subclasses? method now
      shows up in the class.

    ext/ruby/yts/yts.rb: moved eval code out of the YAML
      module.
    ext/ruby/yts/*.yml: prepend YAML module onto all
      code that uses Stream, Omap, etc.

    lib/implicit.re: were 'y' and 'n' seriously omitted??

    lib/node.c: added syck_seq_assign.