Lowered the default OPT_READ_TIMEOUT for Redis

* This should probably be low for the case of a server that is
  quick to accept connections but slow to do anything.
* Made the client class handle blocking operations sanely
  by automatically boosting/lowering the timeout value.

Change-Id: Idea083b843f7eb558d2daf249deea853c9ec43ae
Merge "Lowered the default OPT_READ_TIMEOUT for Redis"