cbcollect_info: Gather block device queue settings
cbcollect_info: Gather block device queue settings

Capture the block device queue settings from /sys for all block
devices on Linux, to aid in diagnosing disk-related issues.

Example output fragment:

    ==============================================================================
    Block device queue settings
    find /sys/block/*/queue/ -type d -exec grep -vH -R xxxx '{}' ';'
    ==============================================================================
    /sys/block/sda/queue/add_random:0
    /sys/block/sda/queue/discard_granularity:0
    /sys/block/sda/queue/discard_max_bytes:0
    /sys/block/sda/queue/discard_max_hw_bytes:0
    /sys/block/sda/queue/discard_zeroes_data:0
    /sys/block/sda/queue/hw_sector_size:512
    /sys/block/sda/queue/io_poll:0
    ...

Change-Id: I7991d87fa7fc2fb588e92867c8c94f73ef8f0a56
Reviewed-on: http://review.couchbase.org/82312
Well-Formed: Build Bot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>
Reviewed-by: Trond Norbye <60edd2ef23891a753f231b0c6f161dc634079a93@gmail.com>
Tested-by: Dave Rigby <a09264da4832c7ff1d3bf1608a19f4b870f93750@couchbase.com>

membase/ns_server,membase/ns_server,membase/ns_server,membase/ns_server,membase/ns_server,membase/ns_server