Class BufferedUpdates

Holds buffered deletes and updates, by docID, term or query for a single segment. this is used to hold buffered pending deletes and updates against the to-be-flushed segment. Once the deletes and updates are pushed (on flush in Lucene.Net.Index.DocumentsWriter), they are converted to a FrozenDeletes instance.

NOTE: instances of this class are accessed either via a private instance on Lucene.Net.Index.DocumentsWriterPerThread, or via sync'd code by Lucene.Net.Index.DocumentsWriterDeleteQueue