Ruby

merges r28550,r28551,r28554 and r28558 from trunk into ruby_1_9_2.¶

• ext/psych/lib/psych/scalar_scanner.rb: making the code more beautiful.
  Thanks nobu!
  --
• ext/psych/lib/psych/visitors/yaml_tree.rb (format_time): nanoseconds
  require more digits when dumping. Thanks akr! [ruby-core:31047]
• test/psych/visitors/test_to_ruby.rb: adjusting tests for nanoseconds
  --
• test/psych/visitors/test_to_ruby.rb (test_time): time test must
  respect non-whole timezone. Thanks akr! [ruby-core:31061]
  --
• ext/psych/lib/psych/scalar_scanner.rb (parse_time): dealing with
  negative partial hour time zones. [ruby-core:31064]
• ext/psych/lib/psych/visitors/yaml_tree.rb: ditto
• test/psych/visitors/test_to_ruby.rb: ditto

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_2@28602 b2dd03c8-39d4-4d8f-98ff-823fe69b080e