Use stable rust (#16)

* Stable rust in setup

* Version WIP

* Update panics

* fix1

* manual fixes

* autofix

* bump

* finish

* More stable fixes

* Stable nb block and editions

src/microbit/Cargo.toml

@@ -1,10 +1,11 @@
 [package]
-name = "microbit"
-version = "0.1.0"
+name = "micro"
+version = "0.2.0"
+edition = "2018"
 
 [dependencies]
 cortex-m-rt="~0.6"
 cortex-m-semihosting="~0.3"
-panic-abort = "~0.3"
+panic-halt = "~0.2"
 panic-semihosting = "~0.5"
-microbit="~0.6"
+microbit="~0.8"

src/microbit/examples/buttons.rs

@@ -1,7 +1,7 @@
 #![no_std]
 #![no_main]
 
-extern crate panic_abort;
+extern crate panic_halt;
 extern crate cortex_m_rt as rt;
 extern crate microbit;
 
@@ -16,7 +16,7 @@ use microbit::hal::serial::BAUD115200;
 fn main() -> ! {
     if let Some(p) = microbit::Peripherals::take() {
         // Split GPIO
-        let mut gpio = p.GPIO.split();
+        let gpio = p.GPIO.split();
         // Configure RX and TX pins accordingly
         let tx = gpio.pin24.into_push_pull_output().downgrade();
         let rx = gpio.pin25.into_floating_input().downgrade();

src/microbit/examples/buttons_poll.rs

@@ -1,7 +1,7 @@
 #![no_std]
 #![no_main]
 
-extern crate panic_abort;
+extern crate panic_halt;
 extern crate cortex_m_rt as rt;
 extern crate microbit;
 

src/microbit/examples/display_blocking.rs

@@ -5,7 +5,7 @@
 extern crate microbit;
 extern crate cortex_m_rt as rt;
 extern crate cortex_m_semihosting as sh;
-extern crate panic_abort;
+extern crate panic_halt;
 
 use core::fmt::Write;
 use rt::entry;