Metrics-layer

What's Changed
* Fix/catch invalid reference error in join graphs by pblankley in https://github.com/Zenlytic/metrics_layer/pull/214


**Full Changelog**: https://github.com/Zenlytic/metrics_layer/compare/v0.12.27...v0.12.28

What's Changed
* fix referenced field in sql not changing join graph issue by pblankley in https://github.com/Zenlytic/metrics_layer/pull/213
* Improve error message on description validation error

**Full Changelog**: https://github.com/Zenlytic/metrics_layer/compare/v0.12.26...v0.12.27

What's Changed
* Fix/null on join issues in non additive dimensions by pblankley in https://github.com/Zenlytic/metrics_layer/pull/211


**Full Changelog**: https://github.com/Zenlytic/metrics_layer/compare/v0.12.25...v0.12.26

What's Changed
* change join to left for non additive dims from inner by pblankley in https://github.com/Zenlytic/metrics_layer/pull/210


**Full Changelog**: https://github.com/Zenlytic/metrics_layer/compare/v0.12.24...v0.12.25

What's Changed
* fix quoting issues with database seeding for searchable tags by pblankley in https://github.com/Zenlytic/metrics_layer/pull/207


**Full Changelog**: https://github.com/Zenlytic/metrics_layer/compare/v0.12.23...v0.12.24

What's Changed
* Make `searchable` tagging REQUIRED for all non-hidden, string type dimensions
* Improve fidelity and features around searchable tagging itself
* Both in PR by pblankley in https://github.com/Zenlytic/metrics_layer/pull/203


**Full Changelog**: https://github.com/Zenlytic/metrics_layer/compare/v0.12.22...v0.12.23