Convert md links to .gmi

[makeworld]

Inspired by this line of code in someone's script:

sed -i'.bak' -e 's/\.md/\.gmi/g' index.gmi

It'd be nice if there was an option that would automatically do this.

[makeworld]

@jansc

[Jan Schreiber]

That would be perfect!

[makeworld]

Added, it will be in the next release.