teaching Psych to deserialize DateTime objects. [Bug #1390]
* ext/psych/lib/psych/visitors/yaml_tree.rb(visit_DateTime): added a
method for serializing DateTime objects.
* ext/psych/lib/psych/scalar_scanner.rb(parse_time): add method for
parsing times objects from a string.
* test/psych/test_date_time.rb: tests for dumping DateTime objects.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@28532 b2dd03c8-39d4-4d8f-98ff-823fe69b080e