Prepare alternatives-2.eclass for the main tree

Following discussion with the original authors, cleanup header and copyrights to
prepare alternatives-2.eclass to be moved to the main tree. Watch out as repoman
will likely complain about the top copyright being 2010-2013 instead of the
usual 1999-2013. Make sure this 2010 start date stays in place in the future.
Fix probable trailing / in EROOT