Tidy up SVN 'eol-style' properties

This is a hopefully comprehensive sweep over the 'current' parts of the
tree (l3kernel/packages/experimental/trial + news/support/validate). 


git-svn-id: http://www.latex-project.org/svnroot/experimental/trunk@4749 de43f980-851b-0410-b2f7-c40aca1f87e0