Added Host related memos.

Change-Id: Idbbce6a72b6f7fecc6691f2af68f4ce40b58ca34
diff --git a/core/api/src/main/java/org/onlab/onos/net/host/HostStore.java b/core/api/src/main/java/org/onlab/onos/net/host/HostStore.java
index 3f1cb23..b27b697 100644
--- a/core/api/src/main/java/org/onlab/onos/net/host/HostStore.java
+++ b/core/api/src/main/java/org/onlab/onos/net/host/HostStore.java
@@ -29,6 +29,7 @@
     HostEvent createOrUpdateHost(ProviderId providerId, HostId hostId,
                                  HostDescription hostDescription);
 
+    // FIXME: API to remove only IpAddress is missing
     /**
      * Removes the specified host from the inventory.
      *
@@ -81,6 +82,7 @@
      * @param ip ip address
      * @return set of hosts with the given IP
      */
+    // FIXME: Switch to IpAddress
     Set<Host> getHosts(IpPrefix ip);
 
     /**