Dub subPackage buildType and output file name

[Stefan Frijters via Digitalmars-d-learn]

Currently I'm using dub for the first time and I've run into two 
problems so far.

1) I have defined buildTypes in dub.json, as well as subPackages. 
However, I want to always build all subPackages in release mode, 
regardless of the --build option I'm using to build the main 
program. I'm not clear if it's possible to do this, and if so, 
how to specify this.

2) I would like the file name of my final executable to depend on 
my chosen --build and --config options (i.e. 
<myexecutable>-<build>-<config>). Is this possible to do?

Kind regards,

Stefan