dbt-spark v0.19.1b2

This is a beta patch release adding support for dbt v0.19.1b2.

$ pip install dbt-spark==0.19.1b2  # or "dbt-spark[ODBC]==0.19.1b2" or "dbt-spark[PyHive]==0.19.1b2"

Under the hood

• update serialization calls to use new API in dbt-core 0.19.1b2 (#150)