More logic improvements for l3build and module/bundle split


git-svn-id: http://www.latex-project.org/svnroot/experimental/trunk@5033 de43f980-851b-0410-b2f7-c40aca1f87e0
Remove a few unfinished l3buld changes

Currently wondering about the top level script: a bit unusual, so do we
need to support this more generally.


git-svn-id: http://www.latex-project.org/svnroot/experimental/trunk@5034 de43f980-851b-0410-b2f7-c40aca1f87e0