..ui.util: adding a simple multiStringSelectionCombo

Change-Id: Iaf2e592add3c8db4ccdbb18291cb7daf6490ac47
..ui.util: use generic and selection index in multipleSelctionCombo

Change-Id: I6c78cc6ae2b67a674c8ef5fb3b9ad5fae70d2598
..ui.util: add support for the user being able to define the format

Change-Id: I453798452d733165df6da829c77d9c40be8b5c8a
Merge branch '3.2.x' of ssh://git@github.com/ControlSystemStudio/cs-studio.git into 3.2.x