* Modifies accessibility bridge to populate new node fields in semantics API.
* Adds additional UTs and fixes logic for breaking up updates for nodes with large values.
* Chaged tests to set node flags using bitwise-or instead of addition.
* Address bug in update size arithmetic.
* Fixes issue in TruncatesLargeValue unit test causing unexpected deletes.
* Fixes expected number of updates in BatchesLargeMessages unit test to reflect expected values now that node states are populated.