Add ability to restrict to older than the release date of some package version

[Cadair]

An interesting use case for timemachine is to install an old environment based on some specific old version. Imagine wanting for example to create an env with astropy 3.2. Being able to pass an argument to the time-machine saying --no-older-than='astropy==3.2' would mean that it finds the release date of that package and uses that, then you could build an env with compatibility with that version of astropy