Change "ID only" to "name or ID" for backup commands

Tested "find_resulce()" can find a backup by name or ID.
But some help messages and doc were "ID only", this patch
modify them.

Change-Id: I22dcc3a0b40f2bafabb6d26498158e2468037312

doc/source/command-objects/backup.rst

@@ -49,7 +49,7 @@ Delete backup(s)
 .. _backup_delete-backup:
 .. describe:: <backup>
 
-    Backup(s) to delete (ID only)
+    Backup(s) to delete (name or ID)
 
 backup list
 -----------
@@ -81,7 +81,7 @@ Restore backup
 .. _backup_restore-backup:
 .. describe:: <backup>
 
-    Backup to restore (ID only)
+    Backup to restore (name or ID)
 
 .. describe:: <volume>
 
@@ -101,4 +101,4 @@ Display backup details
 .. _backup_show-backup:
 .. describe:: <backup>
 
-    Backup to display (ID only)
+    Backup to display (name or ID)

openstackclient/volume/v1/backup.py

@@ -76,7 +76,7 @@ class DeleteBackup(command.Command):
             'backups',
             metavar='<backup>',
             nargs="+",
-            help=_('Backup(s) to delete (ID only)'),
+            help=_('Backup(s) to delete (name or ID)'),
         )
         return parser
 
@@ -150,7 +150,7 @@ class RestoreBackup(command.Command):
         parser.add_argument(
             'backup',
             metavar='<backup>',
-            help=_('Backup to restore (ID only)')
+            help=_('Backup to restore (name or ID)')
         )
         parser.add_argument(
             'volume',
@@ -177,7 +177,7 @@ class ShowBackup(command.ShowOne):
         parser.add_argument(
             'backup',
             metavar='<backup>',
-            help=_('Backup to display (ID only)')
+            help=_('Backup to display (name or ID)')
         )
         return parser
 

openstackclient/volume/v2/backup.py

@@ -147,7 +147,7 @@ class RestoreBackup(command.ShowOne):
         parser.add_argument(
             "backup",
             metavar="<backup>",
-            help=_("Backup to restore (ID only)")
+            help=_("Backup to restore (name or ID)")
         )
         parser.add_argument(
             "volume",