title: knex migration:latest cannot connect while psql works fine
body: <p>I need help figuring out why I can't run knex migration on my local machine 
   using. It seems that knex has some trouble connecting to the postgres database. Running <code>knex migration:latest</code> in the terminal gives me this error:</p>
  
  <pre><code>⇒  knex migrate:latest
  Using environment: development
  Error: Unable to acquire a connection
  at Client_PG.acquireConnection (/Users/moldot/prjx-albert/server/node_modules/knex/lib/client.js:332:40)
  at Runner.ensureConnection (/Users/moldot/prjx-albert/server/node_modules/knex/lib/runner.js:233:24)
  at Runner.run (/Users/moldot/prjx-albert/server/node_modules/knex/lib/runner.js:47:42)
  at SchemaBuilder.Target.then (/Users/moldot/prjx-albert/server/node_modules/knex/lib/interface.js:39:43)
  at Migrator._ensureTable (/Users/moldot/prjx-albert/server/node_modules/knex/lib/migrate/index.js:256:66)
  at Migrator._listCompleted (/Users/moldot/prjx-albert/server/node_modules/knex/lib/migrate/index.js:405:17)
  </code></pre>
  
  <p>I'm using postgres on my local Macbook. This is my knexfile:</p>
  
  <pre><code>var PostgressConnectionStringParser = require('pg-connection-string');
  
  module.exports = {
    heroku: {
      client: 'pg',
      connection: process.env.DATABASE_URL,
      migrations: {
        directory: "migrations",
        tableName: "migrations",
      },
    },
    development: {
      client: "pg",
      host: "localhost",
      port: 5432,
      username: "moldot",
      database: "c_dev",
      migrations: {
        directory: "migrations",
        tableName: "migrations",
      },
      ssl: true,
    },
  }
  </code></pre>
  
  <p>Running <code>psql</code> works fine:</p>
  
  <pre><code>⇒  psql -h localhost -p 5432 -U moldot -d c_dev
  psql (10.1, server 9.5.4)
  Type "help" for help.
  
  c_dev=#
  </code></pre>
  
  <p>I'm running the command in the same directory that knexfile.js is in. Thank you!</p>