Add weighted averages report to web ver

[ZIMkaRU]

This PR adds the Weighted Averages report to the web version. The main part of logic moves to the bfx-report and the behavior is the same as in the previous PR #246

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The idea is: to move the main logic to the bfx-report and extend WeightedAveragesReport service and override _getTrades method to fetch data from DB instead of the bfx-api-v2

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Breaking changes

Response example, it returns nextPage: false to have the same response as in hosted ver:

{
  "jsonrpc": "2.0",
  "result": {
    "nextPage": false, // for framework mode, it should be always `false`
    "res": [
      {
        "symbol": "tUSTUSD",
        "buyingWeightedPrice": 1.12345,
        "buyingAmount": 12345,
        "sellingWeightedPrice": 1.12345,
        "sellingAmount": -12345,
        "cumulativeWeightedPrice": 1.12345,
        "cumulativeAmount": 12345
      }
    ]
  },
  "id": null
}

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Depends on this PR:

• Add weighted averages report to web ver bfx-report#289

[ezewer]

looks good to me!