Add New Protip!

Hi,

So in the pull request section every user has there is a Protip sentence a little bit lower from the pr content. So there is the protip about clicking in g and p to go to pull request, but why not add a p and i to go to issue. If you do that it will go to issue, but there is no protip shown for that.

Further more you could add a p and m to go to the marketplace section and also a p and e to go to the explore section.

I think this will be a very good idea to implement + it saves Github users some time.

Regards,

Hugo.