Created by: andreasschroth
This section is meaningless and doesn't serve any purpose.
To give some more context: The branch alias is good for mapping dev-master (which is the latest dev version of a project) to a specific development branch. But if your master branch is always the latest dev version (as it is the case with Bootstrap), no mapping is needed.
Only problem could be, if another package is requiring a specific version and that conflicts with dev-master (on the master) branch if there's no alias set. But I would say this is VERY unlikely with a project like Bootstrap.
See also https://getcomposer.org/doc/articles/aliases.md#branch-alias .