Replaced QmlTexture by Quick3DTexture

Separated Texture from TextureData. Quick3DTexture is a sublcass of
Quick3DNode and Texture. This is part of a serie of patches aimed at specifying
how Uniforms and Textures are going to be defined from QML.

Change-Id: Ia1a9acfc4d9b07299a103bdbbffcc34aa4b79177
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>
QLoggingCategories added to Core

Change-Id: I1ebdbe809f19e9a158b9a2e4ec351e8842c0c845
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>
QQmlListProperty<Parameter> in Quick3DTechnique

Added a list property for Parameters in Quick3DTechnique so that parameters
can be specified from QML. A follow up patch will expose GL types as an enum
that can be used from QML.

Change-Id: I743f08e64c8e43b9b1ca85295c14b6e8f45840b2
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>
Parameter properties for QML use

GL types exposed as an enum so that it can be used on the QML side.

Change-Id: I2039b0a9aa31a7cabccd64f5a0a5031684cb43f8
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>
Added multiviewport example

Change-Id: I04f20d6c46891ebd3a7b550c181a3e554f30a384
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>