[DOC BLD FIX] Add missing glossaries

This patch added missing glossaries for admin documents.

Change-Id: I7f0112de51e335cfe6522e6878b38b88074b7de7

doc/source/common/glossary.rst

@@ -0,0 +1,24 @@
+========
+Glossary
+========
+
+This glossary offers a list of terms and definitions to define a
+vocabulary for Cinder concepts.
+
+.. glossary::
+
+    Logical Volume Manager (LVM)
+
+        Provides a method of allocating space on mass-storage
+        devices that is more flexible than conventional partitioning
+        schemes.
+
+    iSCSI Qualified Name (IQN)
+
+        IQN is the format most commonly used for iSCSI names, which uniquely
+        identify nodes in an iSCSI network.
+        All IQNs follow the pattern iqn.yyyy-mm.domain:identifier, where
+        'yyyy-mm' is the year and month in which the domain was registered,
+        'domain' is the reversed domain name of the issuing organization, and
+        'identifier' is an optional string which makes each IQN under the same
+        domain unique. For example, 'iqn.2015-10.org.openstack.408ae959bce1'.

doc/source/index.rst

@@ -91,3 +91,11 @@ Indices and tables
 * :ref:`genindex`
 * :ref:`modindex`
 * :ref:`search`
+
+Glossary
+========
+
+.. toctree::
+   :maxdepth: 1
+
+   common/glossary.rst