Improved Object pool test
Merge remote-tracking branch 'GitHub-void/1.4' into 1.4
Added some missing annotations
Fixed ID resolving

There was a problem in resolving the IDs that came up in some cases
and caused illegal IDs to be generated. Now there is a proper ID
overlap detection implemented. Its slightly more time consuming,
but as the resolving is done once when the elements are created and
too long IDs slow done the event handling it does not really matter.

Also there is now a test case that validates correct ID creation.
Added some missing annotations
Added some fail-saves for adding and removing child elements
Handle children storage corruption in element

The children storage of the element got corrupted in case the ID of a
element got changed after it was added to its parent. In this case it
was likely to happen that the element couldn't be located anymore in
the tree set used to maintain the render order.

Now the elements reports any change of the ID to its parent to give
it the chance to update the rendering order as needed.
Merge pull request #180 from mkaring/1.4

Fixing more bugs