Depend on newer asetus version

We are doing this in sql.rb

:user => @cfg.sql.user?
:password => @cfg.sql.password?

As 'asetus' will accept arbitrary chain

@cfg.sql.one.two.three

it is clear that 'one' or 'two' cannot _ever_ return nil/false,
otherwise you cannot create 'three'.

So if there isn't value of one/two, instance of 'asetus' is returned,
upon which we can build two, and then tree'.

one?, two?, three? version existed in old asetus, as strict boolean test

@cfg.sql.one? would return true, false or nil

In newer version, instead of returning true, it returns actual value.