[FEATURE] Add caching functionality to LambdaColumn

[seyuboglu]

I’m envisioning is something in between a map and a LambdaColumn where the computation happens lazily but is cached once it’s computed. Right now, it’s either you do it all up front or you don’t get caching.

This idea was raised @ANarayan who pointed out that it would be helpful for caching feature preprocessing in NLP pipelines.