make use of the newer, better, remote helpers for prepare+create OSD

This changeset goes over the prepare and create functions in OSD and updates them to use the new remote logging and remote exception handlers that `install` is using.

Much leaner/readable functions \o/

Example output:

    $ ceph-deploy osd prepare node1:/tmp/osd1
    [ceph_deploy.osd][DEBUG ] Preparing cluster ceph disks node1:/tmp/osd1:
    [ceph_deploy.osd][INFO  ] Distro info: Ubuntu 12.04 precise
    [ceph_deploy.osd][DEBUG ] Deploying osd to node1
    [node1][INFO  ] write cluster configuration to /etc/ceph/{cluster}.conf
    [node1][INFO  ] Running command: udevadm trigger --subsystem-match=block --action=add
    [ceph_deploy.osd][DEBUG ] Preparing host node1 disk /tmp/osd1 journal None activate False
    [node1][INFO  ] Running command: ceph-disk-prepare --cluster ceph -- /tmp/osd1