Tool/ContributionOpener: Moved its content (DirectoryFileHandler class) to...
Tool/ContributionOpener: Moved its content (DirectoryFileHandler class) to ContributionTool as this is not a Tool. As this is only used in ContributionTool, it does not seem necessary to create a separate module for that. Also: * Fix undefined variable `splitport`. * Use cStringIO instead of StringIO (as the rest of ContributionTool code does).