doc: Rework the persistence index.

wiki/src/doc/first_steps.index.mdwn

@@ -12,9 +12,9 @@
     - [[Tor Bridge Mode|first_steps/startup_options/bridge_mode]]
     - [[Windows Camouflage|first_steps/startup_options/windows_camouflage]]
   - [[Introduction to GNOME and the Tails desktop|first_steps/introduction_to_gnome_and_the_tails_desktop]]
-  - [[Persistent Storage|first_steps/persistence]]
-    - [[Warnings About the Persistent Storage|first_steps/persistence/warnings]]
-    - [[Create & Configure the Persistent Storage|first_steps/persistence/configure]]
-    - [[Enable & Use the Persistent Storage|first_steps/persistence/use]]
-    - [[Delete the Persistent Storage|first_steps/persistence/delete]]
+  - [[Persistence|first_steps/persistence]]
+    - [[Warnings About Persistence|first_steps/persistence/warnings]]
+    - [[Create & Configure the Persistent Volume|first_steps/persistence/configure]]
+    - [[Enable & Use the Persistent Volume|first_steps/persistence/use]]
+    - [[Delete the Persistent Volume|first_steps/persistence/delete]]
   - [[Report a bug|first_steps/report_a_bug]]

wiki/src/doc/first_steps/persistence.mdwn

-[[!meta title="Persistent Volume"]]
+[[!meta title="Persistence"]]
 
 If you use Tails, version 0.11 or later, from a USB stick, you can create a
 persistent volume in the free space left on the USB stick by the <span
@@ -22,7 +22,7 @@ each time you start Tails.
 How to Use the Persistent Volume
 =================================
 
-- [[Warnings About the Persistent Volume|first_steps/persistence/warnings]]
+- [[Warnings About Persistence|first_steps/persistence/warnings]]
 - [[Create & Configure the Persistent Volume|first_steps/persistence/configure]]
 - [[Enable & Use the Persistent Volume|first_steps/persistence/use]]
 - [[Delete the Persistent Volume|first_steps/persistence/delete]]

wiki/src/doc/first_steps/persistence/warnings.mdwn

-[[!meta title="Warnings About the Persistent Volume"]]
+[[!meta title="Warnings About Persistence"]]
 
 [[!toc levels=1]]