Doc: Update information about sidebars

You can toggle both the left and right sidebar. The
sidebaricon.png file was renamed as leftsidebaricon.png,
because a rightsidebaricon.png was added.

Change-Id: I9e00917dc26acc1284c51398606194b982e9234e
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

doc/src/howto/creator-tips.qdoc

@@ -132,13 +132,19 @@
 
     For more information, see \l{Using Command Line Options}.
 
-    \section1 Showing and Hiding the Sidebar
+    \section1 Showing and Hiding Sidebars
 
-    To toggle the sidebar in the \uicontrol Edit and \uicontrol Debug modes, click
-    \inlineimage sidebaricon.png
-    or press \key Alt+0 (\key Cmd+0 on \macos).
+    You can toggle the left and right sidebar in some \QC modes.
 
-    For more information on using the sidebar, see
+    To toggle the left sidebar, click \inlineimage leftsidebaricon.png
+    (\uicontrol {Hide Left Sidebar/Show Left Sidebar}) or press \key Alt+0
+    (\key Cmd+0 on \macos).
+
+    To toggle the right sidebar, click \inlineimage rightsidebaricon.png
+    (\uicontrol {Hide Right Sidebar/Show Right Sidebar}) or press
+    \key Alt+Shift+0 (\key Cmd+Shift+0 on \macos).
+
+    For more information on using the sidebars, see
     \l {Browsing Project Contents}.
 
     \section1 Moving To Symbols

doc/src/howto/creator-ui.qdoc

@@ -112,14 +112,15 @@
 
     \section1 Browsing Project Contents
 
-    The sidebar is available in the \uicontrol Edit and \uicontrol Debug modes, and with a
-    different set of views in the \uicontrol Design mode. Use the
-    sidebar to browse projects, files, and bookmarks, and to view the class
-    hierarchy.
+    A left and right sidebar are available in most \QC modes. The availability
+    of the sidebars and their contents depend on the mode.
+
+    In the \uicontrol Edit mode, you can use the sidebars to browse projects,
+    files, and bookmarks, and to view the class hierarchy.
 
     \image qtcreator-sidebar.png
 
-    You can select the content of the sidebar in the sidebar menu (1):
+    You can select the contents of the sidebars in the sidebar menu (1):
 
     \list
 
@@ -151,15 +152,18 @@
     For more information about the sidebar views that are only available in
     \QMLD, see \l{Using Qt Quick Designer}.
 
-    You can change the view of the sidebar in the following ways:
+    You can change the view of the sidebars in the following ways:
 
     \list
 
-        \li To toggle the sidebar, click \inlineimage sidebaricon.png
-            (\uicontrol {Hide Sidebar/Show Sidebar}) or press \key Alt+0
-            (\key Cmd+0 on \macos).
+        \li To toggle the left sidebar, click \inlineimage leftsidebaricon.png
+            (\uicontrol {Hide Left Sidebar/Show Left Sidebar}) or press
+            \key Alt+0 (\key Cmd+0 on \macos). To toggle the right
+            sidebar, click \inlineimage rightsidebaricon.png
+            (\uicontrol {Hide Right Sidebar/Show Right Sidebar}) or press
+            \key Alt+Shift+0 (\key Cmd+Shift+0 on \macos).
 
-        \li To split the sidebar, click \inlineimage splitbutton_horizontal.png
+        \li To split a sidebar, click \inlineimage splitbutton_horizontal.png
             (\uicontrol {Split}). Select new content to view in the split view.
 
         \li To close a sidebar view, click \inlineimage splitbutton_closetop.png