[BUG] Default composer.json in newly generated themes does not validate.

[goranalkovic-infinum]

The private and version keys shouldn't be there, it fails config validation.

"license": "proprietary", can be added instead per-project, if needed.

[mbmjertan]

I would suggest not setting any composer project metadata apart from require, require-dev, scripts and mandatory keys.

[iruzevic]

not relevant anymore