Merged 13767, 13768, 13769, and 13770 from trunk.
	* lib/xmlrpc/parser.rb (XMLRPC::Convert::dateTime): Fixing a bug that
	  caused time zone conversion to fail for some ISO 8601 date formats.
	  [ruby-Bugs-12677]
	* lib/xmlrpc/client.rb (XMLRPC::Client#do_rpc): Explicitly start
	  the HTTP connection to support keepalive requests. [ruby-Bugs-9353]
	* lib/xmlrpc/client.rb (XMLRPC::Client#do_rpc): Improving the error
	  message for Content-Type check failures. [ruby-core:12163]
	* lib/xmlrpc/utils.rb (XMLRPC::ParseContentType#parse_content_type):
	  Making Content-Type checks case insensitive. [ruby-Bugs-3367]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_8_6@16907 b2dd03c8-39d4-4d8f-98ff-823fe69b080e