Merge pull request #40 from chinoto/patch-2

Add .cargo/config.toml to simplify build command

Author: stappersg

.cargo/config.toml

@@ -0,0 +1,9 @@
+[build]
+target = "avr-atmega328p.json"
+
+[unstable]
+build-std = ["core"]
+
+# Cargo versions before 2021-02-23 won't recognize this: https://github.com/rust-lang/cargo/pull/9175
+[env]
+AVR_CPU_FREQUENCY_HZ = 16000000