DO JUMP fixes

This is the long overdue fix for the annoying #1196:

    Unable to read from Micro SD

It also fixes the error where the navigator would not continue a mission after the DO JUMPs are finished.

Along the lines come some whitespace and verbose info fixes, and an unused function definition.

Please review, it has been tested in HIL.
No this limit is to prevent the function to get stuck when a DO JUMP points to another DO JUMP so that it ends up cycling. After 10 (arbitrary) tries it will give up and return false.