Adding more file formats

As you can see in my 'screensos' source forge project, I have been very active over the last few months.

I have lately added support for png files in FilePng and xml files in FileXml.
I am adding a lot of formats to make use of them in various sub projects.

I have also done a lot of refactoring and tweaking of existing components.
I know that Screens is lacking a lot of documentation. Because I am still in the development stage, I am focusing on the development since the documentation can be added later. It does keep this project under the radar (which I can see just from the page views) but I am fine with that since its not in a usable form anyway at the moment.