glom.grouping is super useful actually

[kurtbrose]

I've been using it like crazy, particularly this kind of construct:

Group({T[0]: [T[1]]})

To collect items, kind of a super-bucketize.

My thoughts on making it official:

• group() helper. -- glom(data, Group(expr)) is equivalent to glom.group(data, expr)
• lift up to init so it is importable from glom
• some docs
• support set as a group target

[kurtbrose]

This basically turns group into "super bucketize", or maybe, "higher dimensional bucketize"