[devhelp] Rename string "Side panel" to "Side Panel"

[Sébastien Wilmet <swilmet src gnome org>]

commit 0f01b77102b3e46f3e48039865daeb3ef4556d86
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Sat May 6 13:04:43 2017 +0200

    Rename string "Side panel" to "Side Panel"
    
    Actually all the strings in the menu are Title Cased. In gedit too.

 src/dh-window.ui |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/dh-window.ui b/src/dh-window.ui
index 5d87e27..521b7ab 100644
--- a/src/dh-window.ui
+++ b/src/dh-window.ui
@@ -90,7 +90,7 @@
     </section>
     <section>
       <item>
-        <attribute name="label" translatable="yes">_Side panel</attribute>
+        <attribute name="label" translatable="yes">_Side Panel</attribute>
         <attribute name="action">win.show-sidebar</attribute>
         <attribute name="stateful">true</attribute>
       </item>