First sketch at a sketch join
implicit evidence must come first
make some things private, avoid divide by zero in Sketched
Random needs seed
add some comments about maxReplicas math
address PR comments
start of a test for sketch joins
also test sketch left join
flesh out sketch join tests; still don't work in local mode
narrowed the problem with running local to TypedSelfLeftCrossTest
switch Sketched to use cross instead of leftCross to avoid bug
remove spurious toList, tweak and comment params on CMS for sketched
Merge pull request #758 from avibryant/avi-sketch-join

First sketch at a sketch join