* improve report visibility
* fix timesheet duration, which breaks validation
* added contributing section in README
* do not allow to change project for existing activities - fixes#2576
* bump theme version to fix FOSUserBundle dependency
* use entity color instead of inherited one - fixes#2200
* open "create new project/activity" form in modal
* re-use action translation for create action title
* do not pre-select first customer in list - fixes#1828
* sort user preferences in sections for better visual grouping
* show comment date only in hover of user avatar
