Doc: Updated the \example and \snippet paths

Also:
- Grouped the example docs under one group. i.e. multimedia-examples
- Moved the \group page here from the qtdoc repo
- Moved the snippets directory under doc from doc/src

Change-Id: I28fb81cf910e58101cd601fb4c440b59b0b0366d
Reviewed-by: Jerome Pasion <jerome.pasion@digia.com>

src/multimedia/recording/qaudiorecorder.cpp

@@ -66,11 +66,11 @@ QT_BEGIN_NAMESPACE
     The QAudioRecorder class is a high level media recording class and contains
     the same functionality as \l QMediaRecorder.
 
-    \snippet doc/src/snippets/multimedia-snippets/media.cpp Audio recorder
+    \snippet multimedia-snippets/media.cpp Audio recorder
 
     In addition QAudioRecorder provides functionality for selecting the audio input.
 
-    \snippet doc/src/snippets/multimedia-snippets/media.cpp Audio recorder inputs
+    \snippet multimedia-snippets/media.cpp Audio recorder inputs
 
     The \l {audiorecorder}{Audio Recorder} example shows how to use this class
     in more detail.

src/multimedia/recording/qmediaencodersettings.cpp

@@ -111,7 +111,7 @@ private:
     and then passing it to a QMediaRecorder instance using the
     QMediaRecorder::setEncodingSettings() function.
 
-    \snippet doc/src/snippets/multimedia-snippets/media.cpp Audio encoder settings
+    \snippet multimedia-snippets/media.cpp Audio encoder settings
 
     \sa QMediaRecorder, QAudioEncoderSettingsControl
 */
@@ -425,7 +425,7 @@ private:
     and then passing it to a QMediaRecorder instance using the
     QMediaRecorder::setEncodingSettings() function.
 
-    \snippet doc/src/snippets/multimedia-snippets/media.cpp Video encoder settings
+    \snippet multimedia-snippets/media.cpp Video encoder settings
 
     \sa QMediaRecorder, QVideoEncoderSettingsControl
 */
@@ -751,7 +751,7 @@ private:
     properties and then passing it to a QCameraImageCapture instance using the
     QCameraImageCapture::setImageSettings() function.
 
-    \snippet doc/src/snippets/multimedia-snippets/media.cpp Image encoder settings
+    \snippet multimedia-snippets/media.cpp Image encoder settings
 
     \sa QImageEncoderControl
 */

src/multimedia/recording/qmediarecorder.cpp

@@ -75,7 +75,7 @@ QT_BEGIN_NAMESPACE
     intended to be used alone but for accessing the media recording functions
     of other media objects, like QRadioTuner, or QCamera.
 
-    \snippet doc/src/snippets/multimedia-snippets/media.cpp Media recorder
+    \snippet multimedia-snippets/media.cpp Media recorder
 
     \sa QAudioRecorder
 */