add offset to Seperation of Scales data handler

DataHandlerSeparationOfScales is currently not able to apply data offset. This is required to use data with t_0=16h in this data handler.

• add offset functionality in self.stride similiar to that in self.shift

added Doing enhancement refactoring labels

created merge request !294 (merged) to address this issue

mentioned in merge request !294 (merged)

mentioned in commit e67e16c3

added .done label and removed Doing label

added merged in Develop label and removed .done label

marked the checklist item add offset functionality in self.stride similiar to that in self.shift as completed

closed with merge request !318 (merged)

mentioned in commit 1634c669