ResourcesManager subclasses

QArrayResourcesManager : QVector based resources manager
QListResourcesManager : QList bases resources manager

Change-Id: I487716749dccb7cb75edc6556d93fc3bb96941ee
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>
RenderClass have a default constructor.

Allows RenderClass to be used by the ResourcesManager

Change-Id: Icad9d26649858bc4a1c1dd61a233a4a46f5163ab
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>
Added missing methods to QAbstractResourcesManager

Change-Id: I50d7d25f0fb4afd8fba247a08b8f937a064030cc
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>
RenderNodesManager

Stores and creates RenderNode instances using a QArrayResourcesManager.
Resources are indexed by Entity uuid.

Change-Id: If3136fd8c5032adbe2ac973290041f75215698cf
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>
CameraManager

Used by the backend to store, using a QListResourcesManager,
backend camera entities create from frontend ones.

Change-Id: I974c3af5591d2750bd7de9f9ccc542bad95ce4f0
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>
Added CameraManager to Renderer and RenderSceneBuilder

Change-Id: Ie8609aab3b2163ed97da47bfc5949388f7ec49cf
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>
RenderSceneBuilder and Renderer using RenderNodesManager

Change-Id: Ie557547aacadcc5b01982761ca53995342d8b790
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>
MeshManager using QArrayResourcesManager

Updated mesh objloader and loadmeshdatajob to work with handles.

Change-Id: Id85d1d796c9851a992d39469e13348c75904ab79
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>
Add QCircularBuffer and test

This is different to QtCore's QRingBuffer. QRingBuffer deals with
raw bytes with a non-contiguous list of QByteArrays. QCircularBuffer
is strongly typed and the data is guaranteed to be stored in a
contiguous block of memory. Although the start/end of the buffer
may not correspond to the start/end of the block of memory once it
has reached capacity and wraps around.

Done-with: Andreas Hartmetz and Marc Mutz
Change-Id: Id03ad308b13fb359604d19474d892ff22c1e9b93
Reviewed-by: Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>