Doc: check language and compliance with Writing Guidelines
Doc: check language and compliance with Writing Guidelines

Task-number: QTBUG-30318

Change-Id: I6117c41344f1a5015a1fa2d4a59950306a719313
Reviewed-by: Venugopal Shivashankar <5756f69ec86de98024d1d912258c6908b6f2ee8f@digia.com>
Reviewed-by: Jerome Pasion <c10995d24f6b454503389e8d00d837aef038985d@digia.com>

kobolabs/qtquickcontrols,drgvond/qtquickcontrols,mizukusak/qtquickcontrols,drgvond/qtquickcontrols,mizukusak/qtquickcontrols,kobolabs/qtquickcontrols,mizukusak/qtquickcontrols,kobolabs/qtquickcontrols,drgvond/qtquickcontrols