Store blockTimestamp from NonFungible.com trade in seconds

[dafky2000]

Currently, NonFungible.com API sales are stored as milliseconds - Date.getTime() returns epoch time in milliseconds as opposed to seconds.

Description

Convert milliseconds to seconds before storage.

Types of changes

Bug fix

Checklist:

• Prefix PR title with [WIP] if necessary.
• Add tests to cover changes as needed.
• Update documentation as needed.
• Add new entries to the relevant CHANGELOG.jsons.

[albrow]

@dafky2000 why do you want to convert this to seconds? Pretty much all other timestamps in the raw schema use milliseconds.

[dafky2000]

Sorry, this is re: An email from @feuGeneA - "nonfungible.com data timestamps inconsistent". Data pulled from the NF API is stored with a date in year 50587 in 0x's database. The initial data export I've provided had blockTimestamp as epoch in seconds but, the API returns a date string.

[feuGeneA]

@dafky2000 thank you for taking such quick action on my email. I very much appreciate the submission.

I've handled this in another part of the code, in an outstanding PR I have.