Configure global lints in .cargo/config

In the absence of a way to configure lints across a workspace, we use
a technique described in EmbarkStudios/rust-ecosystem#68.

This allows us to move the lints that should unconditionally apply
to all crates to this one config, unblocking the split up of the mega
crate into multiple smaller ones.

.cargo/config.toml

@@ -4,3 +4,11 @@ linker = "aarch64-linux-gnu-gcc"
 [alias]
 dev-maker = "run --bin maker -- testnet"
 dev-taker = "run --bin taker -- --maker localhost:9999 --maker-id 10d4ba2ac3f7a22da4009d813ff1bc3f404dfe2cc93a32bedf1512aa9951c95e testnet" # Maker ID matches seed found in `testnet/maker_seed`
+
+# Inspired by https://github.com/EmbarkStudios/rust-ecosystem/pull/68.
+[build]
+rustflags = [
+  "-Wclippy::disallowed_method",
+  "-Wclippy::dbg_macro",
+  "-Wunused-import-braces",
+]

daemon/src/lib.rs

@@ -1,6 +1,5 @@
 #![cfg_attr(not(test), warn(clippy::unwrap_used))]
-#![warn(clippy::disallowed_method)]
-#![warn(clippy::dbg_macro)] // should be used only as a temporary debugging tool
+
 use crate::bitcoin::Txid;
 use crate::bitmex_price_feed::QUOTE_INTERVAL_MINUTES;
 use crate::model::cfd::Order;