Translation propagation/distribution

**Is your feature request related to a problem? Please describe.**
Currently, translation propagation is configured per component and affects components within project. In some cases it does not work well:

* for private instances propagation across projects might be needed ([LibreOffice](https://weblate.documentfoundation.org/))
* the component settings is probably not the place people would look for this setting

**Describe the solution you'd like**
Proposals welcome. It could be done by addon, but I'm not sure it's a good approach here.