Convert webvfx filter to QML

It took a few maneuvers for this one.

QML doesn't have native support for tooltips (except for Button, go figure). For other filters, some tooltips got lost during the conversion process. But for this one, it seems the tooltips are important. So I created a crude ToolTip component and tried to match the native look of tooltips the best that I could.

Also, it might be a good time to discuss the organization of files in src/qmltypes. Maybe QmlFile and QmlHtmlEditor should be moved or renamed? I'm open to comments.
Why not Qt.ToolTip? This combination of flags is doing some slightly funky things on OS X 10.9. Based on my experience with some window-related things, I anticipate potentially more problems on 10.7. I have not tested on other platforms yet.