[price-service] Rust implementation of a P2P price service. (#694)

* price_service: add Rust implementation of P2P price service.

* price_service: formatting hook and removes junk

* price_service: add TODO regarding build.rs hacks

* price_service: allow CGo to link resolv on mac

Author: Reisen

.pre-commit-config.yaml

@@ -58,3 +58,9 @@ repos:
         entry: cargo +nightly clippy --manifest-path ./target_chains/cosmwasm/Cargo.toml --tests --fix --allow-dirty --allow-staged -- -D warnings
         pass_filenames: false
         files: target_chains/cosmwasm
+      - id: cargo-fmt-price-service
+        name: Cargo format for Rust Price Service
+        language: "rust"
+        entry: cargo +nightly fmt --manifest-path ./price_service/server-rust/Cargo.toml --all -- --config-path rustfmt.toml
+        pass_filenames: false
+        files: price_service/server-rust

price_service/server-rust/.gitignore

@@ -0,0 +1,7 @@
+# Ignore Rust build artifacts
+/target
+
+# Ignore Protobuf build artifacts
+src/network/p2p.pb.go
+src/network/p2p.proto
+tools/