maint: update copyright years to 2014

commandline-fu:
    git ls -z \
       | grep -zZE '\.(c|cpp|h|am|ac)$' \
       | xargs -0 sed -i '/copyright.*gymrek/Is/2011 /2011-2014 /'
Merge pull request #48 from agordon/fix/copyright-updates

maint: update copyright years to 2014