function intialize(properties) {
        if(db === undefined) {
            db = require('knex')({
                client: 'pg',
                connection: {
                    user: properties.user,
                    host: properties.host,
                    database: properties.database,
                    password: properties.password,
                    port: properties.port,
                }
            })
        }
    }
Creates a connection pool to the database.
The Pool manages the client connections to allow for
multiple concurrent connections to the database.

@param {ConnectionProperties} properties 
@returns {void}