Merge pull request #940 from catsby/show_pg_psql_name

Show HEROKU_POSTGRESQL_COLOR name when connecting via pg:psql
Friendlier, more useful pg:ps output
Merge pull request #948 from deafbybeheading/better-pg_ps-output

Friendlier, more useful pg:ps output
Permit the usage of ENV["PGPORT"] to change localhost port
Teach CLI to figure out a default Heroku Postgres plan for fork/follow/rollback

Default to primary database plan if no plan specified

Good to default to what you already have if you don't specify a :plan