Fixed T29550 - load save label presets
Summary:
+ refactored the save/load code into the module
Fixes T29550.
Test Plan: code review; application test (saving and loading presets should work now)
Reviewers: O1 MITK Reviewer Group I, kislinsk
Reviewed By: O1 MITK Reviewer Group I, kislinsk
Subscribers: kislinsk
Maniphest Tasks: T29550
Differential Revision: https://phabricator.mitk.org/D814