We should add support for new format .cfx, which will be a zipped XML.
TODO:
1. by default when you save project configuration using File dialog they will be saved to .cfx file. There will be no .xml option
2. when loading config using File load, there will be option to load both .xml and .cfx extensions and it will load it according to this.
3. project config stored in project folder (/user/projects/Builder etc.) should be ideally also saved as .cfx, but if this will be slover or cause problems, they can still be saved into plain .xml format.
.cfx format will then be used only for Load/Save config using file dialog.
Uze Java ZipFile, not JarFile, we don't need to save also manifest.