threadteam 0.3.0

Scoped CPU thread-team placement token: a Pool and a non-Clone Exec with fork, for_ranges, external and broadcast; no Rayon type in the public API.
Documentation
kind,width,ns
team/hot,2,935.7
team/gap1ms,2,5708.0
team/gap10ms,2,6250.0
team/gap300ms,2,34916.0
team/fork-hot,2,1329.7
team/hot,4,766.6
team/gap1ms,4,5417.0
team/gap10ms,4,5083.0
team/gap300ms,4,42416.0
team/fork-hot,4,823.5
team/hot,6,572.2
team/gap1ms,6,6083.0
team/gap10ms,6,6375.0
team/gap300ms,6,85167.0
team/fork-hot,6,609.8
plain/outside-hot,2,12531.8
plain/outside-gap1ms,2,11917.0
plain/outside-gap10ms,2,33334.0
external/outside-hot,2,12077.0
external/outside-gap1ms,2,14792.0
plain/in-pool,2,36.3
plain/outside-hot,4,12191.9
plain/outside-gap1ms,4,21750.0
plain/outside-gap10ms,4,37250.0
external/outside-hot,4,10595.0
external/outside-gap1ms,4,19250.0
plain/in-pool,4,117.2
plain/outside-hot,6,11575.5
plain/outside-gap1ms,6,28458.0
plain/outside-gap10ms,6,45250.0
external/outside-hot,6,10564.1
external/outside-gap1ms,6,17250.0
plain/in-pool,6,218.5