Charts need control over axis labels

[eobermuhlner]

It MUST be possible to control the axis (value labels, ticks, ...) through properties.
The default settings should be null so that the underlying chart library can use its own defaults.

Specific charts MAY use heuristics to control the axis (if not set by user).
For example a matrix without axis values creates integer values for the axis.
In this case the chart SHOULD reduce the axis value labels and ticks to integer values.