Lib.rs

This crate provides Gravity proto definitions in Rust and also re-exports cosmos_sdk_proto for use by downstream crates. By default around a dozen proto files are generated and places into the prost folder. We could then proceed to fix up all these files and use them as the required dependencies to the Gravity file, but we chose instead to replace those paths with references ot upstream cosmos-sdk-proto and delete the other files. This reduces cruft in this repo even if it does make for a somewhat more confusing proto generation process.