Whitelist vendor classes for aliasing

[jasonvarga]

I'm frequently using Tinker to deal with classes from a package, but the aliasing doesn't happen for classes within vendor.

How about config array that whitelists some classes (and/or namespaces).

'alias' => [
   'Statamic\Entries\Entry',
]

I'm happy to PR this myself, but just wanted to ask before doing so.

[driesvints]

Yeah could be cool I think 👍

[zagreusinoz]

We used to be able to do this with Tinx, however that package is now deprecated so would be great for this to be part of Tinker.

[driesvints]

@zagreusinoz feel free to send in a pr