Use generic stand-in for contributors/developers

[eneufeld]

We should use "Eclipse emf.cloud Project" as the generic stand-in for all committers and contributors in all poms and package.jsons to avoid having to manually maintain it.
E-mail address: https://accounts.eclipse.org/mailing-list/emfcloud-dev
Web-site the project page: https://projects.eclipse.org/projects/ecd.emfcloud

For details see the discussion in eclipse-glsp/glsp#246