Extension and Refactoring of Edit function

[Pawana93]

Story: As a user I would like to edit informations of my project, without loosing data or go the way of deleting the old and reinsert the new. I want "on-the-fly" edit of data.

After implementation of Issue #22 the old project is stored in a variable, deleted from the list, manipulated the values and created a new project with the manipulated values.

This has to be done in the refactoring process, for better usability

[Pawana93]

New Issue detected: If I edit the tag, a complete new Project is created. This issue has to be fixed