Review s3a prefetching input stream retry code; synchronization

Need to review S3A prefetching stream retry logic

• no attempt to retry on unrecoverable errors
• do try on recoverable ones
• no wrap of retry by retry.
• annotate classes with Retries annotations to aid the review.

a key concern has to be that transient failure of prefetch is recovered from; things like deleted/shortened file fails properly on the next read call

the other issue is: review all thread safety. the outer stream appears thread safe, so review to make sure that is sufficient