Update internal README

[orbitronhd]

The app itself has it's own git repo which contains a README.md.
It currently shows a default Flutter readme template. This has to be updated with the working of the actual application.

[orbitronhd]

The readme file has been updated based on the work on branch 'homepage'

[orbitronhd]

Open for the next change in file structure.

[orbitronhd]

Open for the next change in file structure.