chore(release): 1.6.0 [skip ci]

# [1.6.0](https://github.com/saltstack-formulas/salt-formula/compare/v1.5.2...v1.6.0) (2020-09-20)

### Features

* enable the metadata grains server by default ([b1d296d2](https://github.com/saltstack-formulas/salt-formula/commit/b1d296d270d3cc06332f569f81ee95fc78d95596))