* ext/psych/lib/psych.rb: update psych version.
    * ext/psych/psych.gemspec: generate new gemspec for new version.

    * ext/psych/lib/psych.rb: calling `yaml` rather than `to_yaml`.
    * ext/psych/lib/psych/nodes/node.rb: Rename `to_yaml` to just `yaml`
      in order to avoid YAML::ENGINE switching from replacing this method.
    * test/psych/helper.rb: fix tests for method name change.
    * test/psych/test_document.rb: ditto
    * test/psych/visitors/test_emitter.rb: ditto

    * ext/psych/lib/psych/scalar_scanner.rb: Match values against the
      floating point spec defined in YAML to avoid erronious parses.
    * test/psych/test_numeric.rb: corresponding test.

    * ext/psych/lib/psych/visitors/to_ruby.rb: ToRuby visitor can be
      constructed with a ScalarScanner.
    * ext/psych/lib/psych/visitors/yaml_tree.rb: ScalarScanner can be
      passed to the YAMLTree visitor.

    * ext/psych/lib/psych/visitors/to_ruby.rb: Define Regexp::NOENCODING
      for 1.9.2 backwards compatibility.
    * ext/psych/lib/psych/visitors/yaml_tree.rb: Fix Date string
      generation for 1.9.2 backwards compatibility.

    * ext/psych/lib/psych/visitors/yaml_tree.rb: emit strings tagged as
      ascii-8bit as binary in YAML.
    * test/psych/test_string.rb: corresponding test.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_3@34017 b2dd03c8-39d4-4d8f-98ff-823fe69b080e