Implement constructor of profile view
Reimplement setModel() in ProfileView

ProfileView reimplements setModel() method
Add a hash map <int, QRectF> to map each row to its rect and a boolean
to allow lazy updating of the map
Add enum in VRDatabase

Add an enum in VRDatabase to represent the layout of columns (used in
index lookup)
Implement function m_calculateRects() in ProfileView