Make fast-louvain importable directly from the git repo

[andrewi66doe]

Hey there, was looking for a rust implementation of the Louvain algorithm and found this very useful. However, since it is not published to crates-io I had to install it directly from the git repo and currently if you try and import it into your Cargo.toml like so:

louvain = { git = "https://github.com/Splines/fast-louvain.git", branch = "main" }

You'll get the following error:

error: no matching package named `louvain-cli` found
location searched: registry `crates-io`
required by package `louvain v0.0.0 (https://github.com/Splines/fast-louvain.git?branch=main#6b5cee07)`
    ... which satisfies git dependency `louvain` of package `megamatch_lambda v0.1.0 (/Users/andrewwalker/Development/kittools-tmp/kittools/crates/megamatch_lambda)`

Seems like it's an issue with package resolution that you won't see locally with the current setup. I made a couple of modifications to the Cargo.toml for the workspace and in the application and cli packages to fix this problem.

Forking with these changes fixed my problem but I figured I'd take a shot at pushing this upstream in case someone else has a similar issue. I understand that this project is still under construction/unfinished but this is a good workaround until a real release is published.

Awesome work by the way!