Bump to 3.1.6
Replace regex with String#include?
Merge pull request #3469 from krasnoukhov/improve-hash-dot-syntax

Improve Mongoid::Attributes::hash_dot_syntax? — replace regex with String#include?
Support limit and skip criteria in Mongoid::Contextual::Aggregable::Mongo
Update changelog
Update changelog
Merge branch '3.1.0-stable' of github.com:mongoid/mongoid into backport-limit-sort-aggregable
bump version