Bumping version to 0.19.8rc2

Bumping version to 0.19.8rc1

Bumping version to 0.19.7

Bumping version to 0.19.7rc1

Bumping version to 0.19.6

Bumping version to 0.19.5

Bumping version to 0.19.4

Bumping version to 0.19.3

Merge pull request dbt-labs#50 from fishtown-analytics/leahwicz/relea…

…se_v0.19.2

Release v0.19.2

Merge pull request dbt-labs#48 from fishtown-analytics/0.20.latest

Bump version: 0.19.2rc2 → 0.20.0rc1