Unbreak delete-an-option

[Rillke]

Update options prior to storing them: Currently, it is not possible to delete an option in a SC/MC question through GUI because it is first deleted but later restored in renegerateOptionSorting().

[Rillke]

@mstuder Would you mind reviewing this pull request?

Reproducing the issue:

• Create a LiveVoting Ojbect
• In Content, click Manage
• Click "Add Question"
• Select Single/MC and confirm
• Add a title, a Question text and at least 2 options
• Click "Create"
• Try to delete one option after the question was saved by clicking (-) next to the option and confirm with "update"

Result:
Option not deleted.

Expected: Option deleted.

[mstuder]

@Rillke, thank you for your pull request-s(!) and your work for live voting! I just fixed the bug with Version 4.3.3 of LiveVoting.

Martin