creator.onSetPropertyEditorOptions - Separate the Allow Add and Allow Remove options

[JaneSjs]

Usage scenario: allow only removing chocie items; prevent adding new choices.

T15563 - Custom composite question type https://surveyjs.answerdesk.io/internal/ticket/details/T15563

Currently, the creator.onSetPropertyEditorOptions event has an option which allows developers to prevent adding and removing items:

options.editorOptions.allowAddRemoveItems a boolean property, true by default. Set it false to disable add/remove items in array properties. For example 'choices', 'columns', 'rows'.

Please consider separating this and creating separate flags for adding/removing items.