[FEATURE] Configuration: Add setFirstDayOfWeek to FormatSettings

There are some special cases, where the application wants to define the
first day of week independent from the user locale. 

Change-Id: Ia372f9e5f72ddd17b869e83251c92f88e3971d1f
CR-Id: 012006153200015038332014
Merge "[FEATURE] Configuration: Add setFirstDayOfWeek to FormatSettings" into rel-1.26