When you start gold with "-" as an argument it will read directly
from stdin, instead of opening a file.
Example calls:
./gold -s dark.json README.md
or
cat README.md | ./gold -s dark.json
When passing a valid GitHub URL instead of a filename to gold,
it will fetch either README.md or README (in that order) from
GitHub and displays the markdown content.
Example:
./gold -s dark.json https://github.com/muesli/beehive