auto open downloads

Description

This patch uses xdg-open to open a download once it has finished.

It simply replaces this:

"xterm -e \"wget --load-cookies ~/.surf/cookies.txt '$0';\"", \

with this:

"ofile=\"$(xdg-user-dir DOWNLOAD)/$(basename \"$0\")\"; wget --load-cookies ~/.surf/cookies.txt -O \"$ofile\" \"$0\"; xdg-open \"$ofile\"", \

in your config.def.h file.