Bump svenstaro/upload-release-action to v2 in rust-release workflow

Bump Cargo.lock

Fix directory issue (#9)

* Update dependencies

* Incorporate changes due tokio reorg & hyper response API change

* Fix startup failure where md file in current workdir.
Root cause was PathBuf::parent() returning an Option<empty String> instead of None when providing a relative path to something in the working directory. The code now takes this (unintuitive) behaviour into account.

* Bump patch version

crates.io v0.2.0