Ability to save entities without triggering events

[syncro]

There can be some cases requiring entites to be saved without emiting EntityChangedEvent and EntitySavingEvent. Possible workarounds can be quite complicated for large projects with big number of entites with lots of fields. So there can be the following solutions:

1. Add EclipseLink Hint to save without events trigger if this is possible
2. Add overload to save methods of DataManager, SaveContext etc. with arugment allowing to disable events triggering