mon: fix read of format_version out of leveldb

The get_version(string, string) is the wrong method; it combines the two
args into a key that is nested inside prefix (so it's prefix/a/b), but we
want perfix/format_version.  Add a method to grab an int for this
particular combo and use that.

This fixes an infinite loop when we actually trigger this code.

Bug introduced by f43c974571beac0c8e54fa699bfa96a1befaf56c.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Joao Eduardo Luis <joao.luis@inktank.com>
ceph: only use readline when in interactive mode

A mere

  import readline

line is dumping this to stdout on CentOS 6.3:

  00000000  1b 5b 3f 31 30 33 34 68  .[?1034h

That confuses non-terminals that read from stdout, so only import when we
are in the interactive mode.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Dan Mick <dan.mick@inktank.com>
osdc/Objecter: fix handling for osd_command dne/down cases

Generalize the map check machinery that the pool dne check uses to also
get the latest map for OSD down/dne checks.  This is better semantics, but
more important fixes the more immediate bug of returning the error code
to the caller from the osd_command -> _submit_command (that is ignored by
pretty much any caller) and then never triggering the callback.

Fixes: #5331
Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Merge remote-tracking branch 'gh/next'