io-cache,quick-read: deprecate volume options with flawed semantics or naming

- performance.cache-size has a flawed semantics, as it's
  dispatched on two independent translators, io-cache
  and quick-read.
- performance.qr-cache-timeout has a confusing name, as
  other options affecting quick-read have an unabbreviated
  "quick-read-..." prefix in their names.

We keep these options with unchanged operation, but in the
help output we indicate their deprecation.

The following better alternatives are introduced:

- performance.io-cache-size to tune cache-size option of io-cache
- performance.quick-read-cache-size to tune cache-size option of
  quick-read
- performance.quick-read-cache-timeout as a preferred synonym for
  performance.qr-cache-timeout

Fixes: #952
Change-Id: Ibd04fb638de8cac450ba992ad8a415154f9f4281
Signed-off-by: Csaba Henk <csaba@redhat.com>

0 files changed, 0 insertions, 0 deletions