Derive auto logMinLimit value

[nickofthyme]

In #916 we added the option of logMinLimit to remove the hardcoded value of 1 add the lower bound of a logarithmic scale.

Ideally, we can determine this value automatically and set the lower bound of the scale to the lower bound of the data.

The solution here is to keep the logMinLimit option and use it if defined, if not we compute it given the data. If the value is indeterminate we could use 1 as a default.

This value also applies to the determination of the baseline of the logarithmic scale for area and bar chart which is defaulted to a value of 1. In this case we should compute the min value and clamp if below 1, this value could also be configurable as logMaxLimit.