reset method
Reset the read/write offsets in the buffer.
If hard is true, reset the _recordedReadCount and
_recordedWriteCount accumulators also.
If hard is false (default), add the current readCount to the
_recordedReadCount and writeCount to the _recordedWriteCount.
The length of the buffer does not change.
Implementation
void reset({bool hard = false}) {
resetRead(hard: hard);
resetWrite(hard: hard);
}