Update QtBluetooth's supported platforms

And correct a minor capitilization mistake.

Change-Id: I2e09d4c45ac6d95fd0069a08f646e65c46e9428a
Reviewed-by: Paul Wicking <paul.wicking@qt.io>
Reviewed-by: Oliver Wolff <oliver.wolff@qt.io>

doc/src/qtmodules.qdoc

@@ -36,7 +36,7 @@
 
     \section1 Qt Essentials
 
-    Qt essentials define the foundation of Qt on all platforms. They are
+    Qt Essentials define the foundation of Qt on all platforms. They are
     available on all supported development platforms and on the tested target
     platforms. They will remain source and binary compatible during Qt 5.
 
@@ -151,7 +151,8 @@
         \li \l[QtBluetooth]{Qt Bluetooth}
         \li All
         \li \l{Qt for Android}{Android},
-        \l{Qt for iOS}{iOS}, \l{Qt for Linux/X11}{Linux} and \l{Qt for macOS}{\macos}
+            \l{Qt for iOS}{iOS}, \l{Qt for Linux/X11}{Linux}, \l{Qt for macOS}{\macos}, and
+            \l{Qt for WinRT}{WinRT}
         \li Provides access to Bluetooth hardware.
     \row
         \li \l[QtCanvas3D]{Qt Canvas 3D}