feat: add per-entity logarithmic override

[mxr]

Adds per-entity logarithmic configuration so mixed-scale graphs work correctly.

Specifying 'secondary' for the y-axis isn't enough for my use-case. I have a graph with two waveforms: one waveform is brightness on the primary y-axis (roughly 1 to 5000), while another waveform is sunrise/sunset on the secondary y-axis (boolean 0/1). With only global logarithmic: true, the sunrise/sunset waveform breaks; this change allows keeping brightness logarithmic while leaving sunrise/sunset linear via entity-level override.

Resolves #862

Current	Example of why logarithmic: true globally doesn't work	Example with the fix

[ildar170975]

Thank you! Will check it soon.
Meanwhile, if you have some spare time, test other PRs; start with recently updated ones. Of course, only if you are interested in the proposed functionality, no obligations))

[ildar170975]

@mxr
Added some observations, please consider.

For me, the whole "graph" functionality (described in a graph.js) is still a complex thing which I am not 100% familiar with.
In this PR there are mostly SIMPLE changes, a global logarithmic option is "augmented" by a a per-entity option.
What probably needs to be at least confirmed - is a building a logarithmic graph itself.
Of course, we may blindly trust the current implementation - but these algorithms should be analysed & improved if needed in future (at least to become "maintainable").

For now, I think this PR achieved it's minimal goal (per-entity option).
@akloeckner - please review when you have a spare time.

[mxr]

Thanks for the feedback. I implemented it in mxr@6518e8b (GitHub seems to be lagging so I amended the prior commit)

What probably needs to be at least confirmed - is a building a logarithmic graph itself.

I have an example in the PR description. Let me know if I misunderstood.

[ildar170975]

I totally understood your example, I meant a technical implementation of the Graph class itself. Repeat, the PR looks fine, but since personally me may not know some details of Graph class, I am not sure that the whole logarithmic thing works properly. Let’s merge and then test.