Update bug report instructions

Closes: #122
Thanks: Patrick Schleizer

grml-debootstrap

@@ -607,7 +607,7 @@ fi
 
 [ "$_opt_version" ] && {
   einfo "$PN - version $VERSION"
-  einfo "Send bug reports to bugs@grml.org or http://grml.org/bugs/"
+  einfo "Report bugs via https://github.com/grml/grml-debootstrap/ or https://grml.org/bugs/"
   eend 0
   exit 0
 }