don't assume existence of $USER database
don't assume existence of $USER database

When run without an argument `psql` assumes that there is a database of
name $USER. This is not always the case. However, generally there will
be a database called `postgres` which gives a db to login into in order
to create the `mimic` database.

fereshteh-razmi/mimic-code,MIT-LCP/mimic-code-sharing,MIT-LCP/mimic-code,MIT-LCP/mimic-code,fereshteh-razmi/mimic-code,fereshteh-razmi/mimic-code,MIT-LCP/mimic-code-sharing,MIT-LCP/mimic-code