Other F# default Seq functions

[lucasteles]

The BCL F# Seq module has some other really helpful functions, do you have plans to implement them? need help/accept PR?

average
averageBy
cache
countBy
distinct
distinctBy
exactlyOne
exists
exists2
forall
forall2
groupBy
iteri
last
maxBy
minBy
nth
pairwise
pick
reduce
skipWhile
sort
sortBy
takeWhile
truncate
tryFind
tryFindIndex
tryPick
windowed
zip3

[dbrattli]

Yes, would love a PR on this. Note that the code should be using curry or curry_flipped style functions instead of the nested (function returning) functions. See here for an example: https://github.com/cognitedata/Expression/blob/main/expression/collections/block.py#L669

[ShalokShalom]

Note: curry_flipped got renamed into curry_flip

#87