With the "Use range_streamer everywhere" (7217b7ab36) seires, all
the user of streaming now do streaming with relative small ranges and
can retry streaming at higher level.
There are problems with timeout and retry at RPC verb level in streaming:
1) Timeout can be false negative.
2) We can not cancel the send operations which are already called. When
user aborts the streaming, the retry logic keeps running for a long
time.
This patch removes all the timeout and retry logic for streaming verbs.
After this, the timeout is the job of TCP, the retry is the job of the
upper layer.
Message-Id: <df20303c1fa728dcfdf06430417cf2bd7a843b00.1503994267.git.asias@scylladb.com>