make x-axis linear in market depth chart

[skzap]

Before:

After:

[skzap]

You might want to ignore some values, other big exchanges seem to do that: https://www.binance.com/fr/trade/ETH_BTC (click on 'Depth' at top right of their chart)

[Vheissu]

@skzap This looks good to me, thanks for this. Do you want to sort out the merge conflict and I can get this one merged in?

[skzap]

Done @Vheissu