Add --deploy to graph-info

[memsharded]

How to do some quick graph info, and extract custom information from the graph, in an extensible way?

• Formatters at the moment are very built-in, and seems difficult to change it
• --deploy only applies to install, so it is necessary to install the binaries, which can be slow
• There are no more global custom generators, only as python_requires
• It could be possible to fork the graph_info command, but seems a bit too much to just do something equivalent to the deployers

On the other hand, I don't love the deploy name, but I don't want to create yet another name for something that is mostly identical