Qt-ify the QtCompositor module

Currently the QtCompositor library and API do not follow the Qt API
naming conventions.  This commit intends to fix these inconsistencies.

filenames start with q
headers containing private API's end in _p
public API classes begin with Q
use the qt namespace macros where necessary

Wayland namespace is now QtWayland
wayland_wrapper classes are now private API's

It's important to make these changes not just for stylistic reasons, but
also because when qmake builds the module in checks for these
conventions to determine how to deploy the include files.

Change-Id: I8bfadeceda92a0f52cb73c704551da75540e7587
Reviewed-by: Paul Olav Tvete <paul.tvete@digia.com>

src/plugins/platforms/wayland/shared/qwaylandmimehelper.cpp

@@ -46,6 +46,8 @@
 #include <QBuffer>
 #include <QImageWriter>
 
+QT_USE_NAMESPACE
+
 QByteArray QWaylandMimeHelper::getByteArray(QMimeData *mimeData, const QString &mimeType)
 {
     QByteArray content;

src/plugins/platforms/wayland/shared/qwaylandmimehelper.h

@@ -46,10 +46,14 @@
 #include <QByteArray>
 #include <QMimeData>
 
+QT_BEGIN_NAMESPACE
+
 class QWaylandMimeHelper
 {
 public:
     static QByteArray getByteArray(QMimeData *mimeData, const QString &mimeType);
 };
 
+QT_END_NAMESPACE
+
 #endif