[glossary] Consolodate project codenames [horizon]

- Combine "Dashboard" entry with "horizon" entry
  - Rename "Dashboard" to "Dashboard (horizon)"
  - Link "horizon" to "Dashboard (horizon)"
  - Make sure description matches project.yaml

Change-Id: I7c88be7c40b177944847349c44fef34877802c9f
Implements: blueprint improve-glossary-usage

doc/arch-design/source/generalpurpose-technical-considerations.rst

@@ -352,7 +352,7 @@ OpenStack core services recommended in a general purpose cloud are:
 
 * :term:`Identity service` (:term:`keystone`)
 
-* :term:`Dashboard` (:term:`horizon`)
+* :term:`Dashboard (horizon)`
 
 * :term:`Telemetry service` (:term:`ceilometer`)
 

doc/common/glossary.rst

@@ -972,10 +972,10 @@ D
       May or may not listen on a TCP or UDP port. Do not confuse with a
       worker.
 
-   Dashboard
+   Dashboard (horizon)
 
-      The web-based management interface for OpenStack. An alternative
-      name for horizon.
+      OpenStack project which provides an extensible, unified, web-based
+      user interface for all OpenStack services.
 
    data encryption
 
@@ -1704,8 +1704,7 @@ H
 
    horizon
 
-      OpenStack project that provides a dashboard, which is a web
-      interface.
+      Codename for the :term:`Dashboard <Dashboard (horizon)>`.
 
    horizon plug-in
 

doc/networking-guide/source/intro.rst

@@ -32,9 +32,9 @@ components:
 * OpenStack :term:`Compute service (nova)` is used to plug each virtual
   NIC on the VM into a particular network.
 
-* OpenStack :term:`Dashboard` (horizon) is used by administrators and tenant
-  users to create and manage network services through a web-based graphical
-  interface.
+* OpenStack :term:`Dashboard (horizon)` is used by administrators
+  and tenant users to create and manage network services through a web-based
+  graphical interface.
 
 .. toctree::
    :maxdepth: 2

doc/ops-guide/source/arch-example-nova-network.rst

@@ -72,8 +72,8 @@ those deviations next.
     The following features of OpenStack are supported by the example
     architecture documented in this guide, but are optional:
 
-    -  :term:`Dashboard`: You probably want to offer a dashboard, but your
-       users may be more interested in API access only.
+    -  :term:`Dashboard <Dashboard (horizon)>`: You probably want to offer
+       a dashboard, but your users may be more interested in API access only.
 
     -  :term:`Block storage <Block Storage service>`:
        You don't have to offer users block storage if their use case only