add command to locate dependency

[JustinDrake]

I'm new to gx and below is my current workflow for hacking a dependency of go-ipfs. Let's say I want to make changes to the dependency go-libp2p-kad-dht, then my steps are:

• Search for the string go-libp2p-kad-dht in package.json
• Copy the corresponding hash (in this case, QmaQrN5Gi5jz2ViKuJ5PU2LXV79D6vGuH7eVQnwxpoRqrd)
• Build the path $HOME/src/gx/ipfs/QmaQrN5Gi5jz2ViKuJ5PU2LXV79D6vGuH7eVQnwxpoRqrd/go-libp2p-kad-dht by doing a paste
• Open my text editor at that path (e.g. sublime $HOME/src/gx/ipfs/QmaQrN5Gi5jz2ViKuJ5PU2LXV79D6vGuH7eVQnwxpoRqrd/go-libp2p-kad-dht)

Adding a command to locate the repository would be very helpful. For example, the command gx locate go-libp2p-kad-dht would return the path $HOME/src/gx/ipfs/QmaQrN5Gi5jz2ViKuJ5PU2LXV79D6vGuH7eVQnwxpoRqrd/go-libp2p-kad-dht.

[whyrusleeping]

For this we have gx deps find, as well as gx deps --tree --highlight=PACKAGE.

Having gx deps find return a path might be nice as an option.