dispatch/dispatch — pull request #71 by iron9light (2012-02-29 09:49:58+00:00)
Title: Fix if system porperty, "https.proxyPort" and etc, is "" but not null.

I have a very strange error.
It's caused by "https.proxyPort" being "", so it cannot be parsed to Int.
When I use `new Http`, I encountered this error. But when I use `Http` object, this error disappeared.

This patch can fix this error.