* feat(pg): implement postgres plugin

* fix: linting

* fix: docker starting not locally

* fix: compile errors from merge

* fix: linting

* refactor: use helper functions for span building

* fix: add callback patching to end span

* fix: add required attributes, address comments

* fix: lint errors

* refactor: start named spans in query handlers

* fix: linting errors

* fix: circleci config, make pg helpers nonexported

* fix: linting

* docs: add supported versions

* fix: pass PG env to spawned container

* fix: remove hardcoded shouldTest

* test: add span tests for pg driver errors

* chore: remove hardcode shouldTest