Store additional OSD information in ZK

Ensures that information like the FSIDs and the OSD LVM volume are
stored in Zookeeper at creation time and updated at daemon start time
(to ensure the data is populated at least once, or if the /dev/sdX
path changes).

This will allow safer operation of OSD removals and the potential
implementation of re-activation after node replacements.

daemon-common/zkhandler.py

@@ -540,7 +540,7 @@ class ZKHandler(object):
 #
 class ZKSchema(object):
     # Current version
-    _version = 7
+    _version = 8
 
     # Root for doing nested keys
     _schema_root = ""
@@ -700,6 +700,12 @@ class ZKSchema(object):
             "node": "/node",
             "device": "/device",
             "db_device": "/db_device",
+            "fsid": "/fsid",
+            "ofsid": "/fsid/osd",
+            "cfsid": "/fsid/cluster",
+            "lvm": "/lvm",
+            "vg": "/lvm/vg",
+            "lv": "/lvm/lv",
             "stats": "/stats",
         },
         # The schema of an individual pool entry (/ceph/pools/{pool_name})