read user ENV settings for both user-env-compile or buildpack-env-arg
quote env vars
remove run_with_env

run supports everything run_with_env does, so let's use that
fix rake detection when DATABASE_URL not present

Introduced `rake_env` to LanguagePack interface. Renamed `default_database_url` to `database_url`.
update changelog
push to github before tagging/releasing
bump to v101
fix github_remote extraction
pass output options to pipe
debug
actually use the blacklist env vars