New Feature - Format date in second to milliseconds(JS)

[jeftarmascarenhas]

When we working with blockchain date, the we set or get date in second but Javascript use date in milliseconds.
It's common we need to create a formating function transform second to milliseconds.

Ex:
javascript
new Date(ethers.toNumber(timestamp) * 1000)

My proposal feature is create a parseDate and formatDate date to date implementing to be easier.

If it's a good idea I can implement this feature.