don't break when invoked without specifying directory
don't break when invoked without specifying directory

invocations like 'python anthracite-web.py' means the dir is
an empty string

jjardel/anthracite,nickman/anthracite,square-root/anthracite,Dieterbe/anthracite,jjardel/anthracite,nickman/anthracite,nickman/anthracite,square-root/anthracite,jjardel/anthracite,Dieterbe/anthracite,Dieterbe/anthracite,square-root/anthracite,nickman/anthracite,jjardel/anthracite,square-root/anthracite,Dieterbe/anthracite