See https://code.google.com/p/plv8js/wiki/PLV8
createdb opendemocracy createdb opendemocracy-test
psql -d opendemocracy -c 'create extension plv8' psql -d opendemocracy-test -c 'create extension plv8'
createlang -d opendemocracy plv8 createlang -d opendemocracy-test plv8