Add support for overriding Created and Last-Modified dates on deploy

[capyvara]

On migration/mirroring use cases, it's useful to be able to change the Created and Last Modified dates of the deployed artifacts, this PR allows to pass up an optional datetime override for both fields.

This is done by adding the X-Artifactory-Created and X-Artifactory-Last-Modified fields

[beliaev-maksim]

can you please add link to JFrog the documentation in PR description add info to the changelog and fix pre-commit issues

[capyvara]

@beliaev-maksim I don't think this is documented, I stole it from their nexus migration code: https://github.com/jfrog/nexus2artifactory/blob/master/nex2art/core/Upload.py

Do you think it's a problem?

[allburov]

@capyvara @beliaev-maksim May be we can add the hack somewhere in the FAQ section in the readme.md ?

I'm not sure that we need to have dedicated parameters for the case, people use it rarely, but we should document this especially because official Artifactory Docs doesn't have the headers.

What do you think?