New empty MCU application template

The new MCU project template added in Qt Creator 10 - based on qmlproject - contains too much content in some cases. While it is a good example to show how to set up and configure all the main parts of an application, it is too complex when all you need is an empty project to start from. In this case, the current template requires unnecessary work to get rid of what's not needed.

We need a new MCU project template with a simpler structure: a single main QML file with a root rectangle and a text item, but without any images, custom fonts, translations, modules, or C++ interfaces.

The new template should be first in the list when creating a new project, that is, it should be the default option.

This template could be referred to as "Empty application".
The previous template should be referred to as "Example application" and appear second in the list.

The template .qmlproject file should keep a set of default settings as in the existing complete app template.
ImageFiles, TranslationFiles, FontFiles nodes should either be removed or kept without any source files if it doesn't cause a code generation error.