Guidelines for better contributions

hello,

we need to have a full guidelines into the developer manual instead of the git

Cheers

changed milestone to %FusionDirectory 1.3.1

added PJ1802-0188 label

closed via commit df68c763

mentioned in commit 5687616c

added PJ2003-0343 label and removed PJ1802-0188 label

added Added label

mentioned in commit df68c763