l3build: A few doc tweaks

Most of these are pretty obvious. On the "binaryfiles" setting, note that this
is about line endings rather than compression (PDFs do compress a bit).


git-svn-id: http://www.latex-project.org/svnroot/experimental/trunk@5139 de43f980-851b-0410-b2f7-c40aca1f87e0
Some updates to Will's draft l3build article


git-svn-id: http://www.latex-project.org/svnroot/experimental/trunk@5140 de43f980-851b-0410-b2f7-c40aca1f87e0
Step l3build version (CTAN snapshot)


git-svn-id: http://www.latex-project.org/svnroot/experimental/trunk@5141 de43f980-851b-0410-b2f7-c40aca1f87e0