Revert "[CL] Use Grid + Repeater instead of a view."

This reverts commit b3a3cb99ef30a63426ac90b5ab45eee79ebb28cb.
[CL] Less magic numbers.
[CL] Fractional amount of points per pixel.
[Util] Keep track of extents in -qml.
[CL] Correctly calculate cell width according to plot extents.
[CL] Fill whole tooltip with mouse area.