Adding support for specifying a DATABASE_URL without a password

[robscott]

Earlier today I found that Knex was not parsing a user from the following DATABASE_URL:

mysql://travis@127.0.0.1:3306/yodel_test

This was because the URL was missing a password. Because pg-connection-string is being used for Postgres connections, this already worked for Postgres URLs. If you want a laugh, feel free to look at my commits from earlier today where I clearly had no idea how I'd broken all our Travis tests by starting to use DATABASE_URL.

PS: Knex is awesome, thanks for all the work on this project.

[rhys-vdw]

Thanks @robscott. 👍