New QCameraInfo class.

The class allows to get the list of available cameras on the system as
well as getting some static information about them such as their unique
ID, display name, physical position and sensor orientation.

This makes QCamera::availableDevices() and QCamera::deviceDescription()
obsolete.

This patch contains the API, documentation and auto-tests but not the
actual implementation by each backend (except for retrieving the default
camera device).

[ChangeLog][QtMultimedia] Added new QCameraInfo class
[ChangeLog][QtMultimedia] QCamera: availableDevices() and
deviceDescription() are deprecated, use QCameraInfo instead

Change-Id: I64fd65729ab26a789468979ed5444ee90bb82cd0
Reviewed-by: Christian Stromme <christian.stromme@digia.com>
VideoOutput: fix autoOrientation with a camera source.

Don't assume the camera frames are always in the same orientation as the
display in its primary orientation. We now take into account the camera
sensor position and orientation to calculate the viewport orientation.

Change-Id: Ib333c87f1804d1010ada42cb757e4fab78d75a04
Reviewed-by: Christian Stromme <christian.stromme@digia.com>
Android: implement QCameraInfoControl.

VideoOutput will now take into account the camera sensor orientation to
adjust the viewport orientation, we don't need to apply a rotation on
the Android Camera anymore.

Change-Id: Ia7639f0a5711ab6cc6f80b9716bc1a6f389499b4
Reviewed-by: Christian Stromme <christian.stromme@digia.com>