mon: mark dir as upstart managed

ceph-disk-activate will now do the same for the osd dir.
new: fix error message when keyring exists

Signed-off-by: Sage Weil <sage@inktank.com>
new: slightly more verbose

Signed-off-by: Sage Weil <sage@inktank.com>
add uninstall, purge

Mirror the platform detection for install.  Obviously this needs cleanup
to support other platforms.

Signed-off-by: Sage Weil <sage@inktank.com>
new: require monitors

It doesn't make much sense to run this command without specifying the
mons, unless you are going to edit the file manually.  If that is the
case, however, we can still require it and they can change the names or
IPs after.

Signed-off-by: Sage Weil <sage@inktank.com>
osd: 'osd COMMAND HOST:...'

Implement prepare, activate, create subcommands.  Create is basically
prepare+activate.

Signed-off-by: Sage Weil <sage@inktank.com>
install: rename *_ubuntu *_debian

It's about APT, not debian vs ubuntu.

Signed-off-by: Sage Weil <sage@inktank.com>
install: include bobtail, cuttlefish in stable release names

No reason not to support the new URLs now, even tho they don't exist yet.

Signed-off-by: Sage Weil <sage@inktank.com>
osd: do not make journal equal to disk when it is left off

Let ceph-disk-prepare handle the default journal logic.  Putting it in
here obscures information, and makes it confusing when you specify a
dir like so:

 ceph-deploy osd foo:/srv/mydir

would turn into

 ceph-disk-prepare /srv/mydir /srv/mydir

which is nonsense.

Signed-off-by: Sage Weil <sage@inktank.com>
discover: pull a ceph.conf from another host

This will let the user discover a remote host so that they can start
managing it.  Probably followed by 'gatherkeys'.

Signed-off-by: Sage Weil <sage@inktank.com>
mon: make create a subcommand

We don't have other subcommands, but this establishes constency with
'osd create ...' and so on.

Signed-off-by: Sage Weil <sage@inktank.com>
cli: verbose by default, -q to shut up

Closes: #3907
Signed-off-by: Sage Weil <sage@inktank.com>
cli: part -n, --dry-run

Signed-off-by: Sage Weil <sage@inktank.com>
new: catch hostname lookup exception

Signed-off-by: Sage Weil <sage@inktank.com>
discover: implement -n

Not so useful, but...

Signed-off-by: Sage Weil <sage@inktank.com>
new: add -n

Say what files will be written, but don't.

Signed-off-by: Sage Weil <sage@inktank.com>
zapdisk: quick comment

Signed-off-by: Sage Weil <sage@inktank.com>
osd: fix no journal case

Behave is journal=None.

Signed-off-by: Sage Weil <sage@inktank.com>
install: generalize for any Debian and Ubuntu

All we need to do is decide to use APT and pass the codename down.

Part of #3920.

Signed-off-by: Sage Weil <sage@inktank.com>
README: update with updated syntax

Signed-off-by: Sage Weil <sage@inktank.com>