Correct license headers

As we heard on the mailing list or in different MP repositories, Eclipse Foundation requires all source files to contain a header like
> Copyright 2016, 2017 by [Legal Entity] and others

Most files here suggest, the initial committer was @agoncal so unlike earlier changes it must not be 
> Copyright 2016 Microprofile and contributors

but
> Copyright 2016 by Antonio Goncalves and others