This commit adds an example how to run the Docker image so the
data is persisted between restarts based on our docker-run.sh
script. It also fixes a typo in the docker-run.sh script where
the default DATA_DIR was not correctly set.
The dblink extension is blacklisted by some cloud-hosting providers and
is an unnecessary dependency for single-node operation. Since we don't plan
to use dblink to implement clustering this PR removes the dependency.
- Directory structure now matches common practices
- Regression tests now run with pg_regress via the PGXS infrastructure.
- Unit tests do not integrate well with pg_regress and have to be run
separately.
- Docker functionality is separate from main Makefile. Run with
`make -f docker.mk` to build and `make -f docker.mk run` to run
the database in a container.
