History client uses the newer api/v2 endpoint

[monsieurleberre]

↪️ Pull Request

CryptoCompare recommends to upgrade the history Api endpoint to use its v2, which apparently gives better data.
The client was still using v1

💻 Examples

🚨 Test instructions

History tests should still be passing

💥 Does this PR introduce a breaking change?

• Yes
• No

The HistoryResponse class doesn't have a list of candle data, but another nested object called HistoryResponseData, which in turn holds that list. This follows the structure of the JSON returned by v2 endpoint.

✔️ PR Todo

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING.md document.
• I have added tests to cover my changes.
• All new and existing tests passed.
  it looks like some tests have been broken for a while, but I have unfortunately no time to fix them at present

[monsieurleberre]

I am not sure I understand why the semantic pull request doesn't like my commits 😬 thanks for your help!