readChunk( data ) {

			const chunk = {};
			chunk.cur = this.position;
			chunk.id = this.readWord( data );
			chunk.size = this.readDWord( data );
			chunk.end = chunk.cur + chunk.size;
			chunk.cur += 6;
			return chunk;

		}
Read next chunk of data.

@method readChunk
@param {DataView} data Dataview.
@return {Object} Chunk of data read.