Change price and volume into indicators

[glowacki-dev]

We may unify API by only leaving dates array and indicators dictionary. This would require to change price and volume into indicators.

{
  dates: [...],
  indicators: {
    price: {
      info: [...],
      close: [...],
      high: [...],
      low: [...],
      open: [...]
    },
    volume: {
      info: [...],
      volume: [...]
    },
    BB: {
      info: [...],
      upperband: [...],
      lowerband: [...]
    },
    ...,
    sentiment: {
      info: [...]
    }
  }
}

This way each indicator will be a dictionary containing info array with tokens and some optional arrays with data used for drawing

[glowacki-dev]

Indicators after unification have been described in https://github.com/nuclearpinguin/Bitreport/wiki/Indicators

[glowacki-dev]

For fib levels we will lose information about fib percentage but it's not really that important right now

[turbaszek]

Should we use the chart's type (uptrend etc.) as a sentiment for now?