[safety] Color of Module Corresponding to the State of the Contained Elements
The color of the module shall be determine by followingfactors:
- if the module contains at least one to be developed element, it shall have TO_BE_DEVELOPED_COLOR;
- if the module contains at least one to be instantiated element, it shall have TO_BE_DEVELOPED_COLOR;
- otherwise, it shall have DEFAULT_BACKGROUND.
(from redmine: issue id 3007, created on 2017-08-02, closed on 2018-02-09)