Remove TryFrom in order to build with stable

Cargo.lock

@@ -44,7 +44,6 @@ name = "bme680-rs"
 version = "0.1.0"
 dependencies = [
  "bitflags 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "byteorder 1.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "embedded-hal 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "i2cdev 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "linux-embedded-hal 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",

Cargo.toml

@@ -5,7 +5,6 @@ authors = ["marcelbuesing <buesing.marcel@googlemail.com>"]
 
 [dependencies]
 bitflags = "1.0"
-byteorder = "1.2"
 embedded-hal = "0.2"
 
 [dev-dependencies]

examples/reading_temperature.rs

@@ -1,11 +1,8 @@
-//extern crate i2cdev;
 extern crate embedded_hal;
 extern crate linux_embedded_hal as hal;
 extern crate bme680_rs;
 
-//use i2cdev::linux::LinuxI2CDevice;
 use bme680_rs::*;
-use std::io;
 use hal::*;
 use std::thread;
 use std::result;

src/lib.rs

@@ -1,12 +1,9 @@
-#![feature(try_from)]
-
 #[macro_use]
 extern crate bitflags;
 extern crate embedded_hal as hal;
 
 use hal::blocking::delay::DelayMs;
 use hal::blocking::i2c::{Read, Write};
-use std::convert::TryFrom;
 
 use std::result;
 
@@ -346,7 +343,7 @@ impl I2CUtil
     where I2C: Read {
         let mut buf = [0; 1];
         match i2c.read(reg_addr, &mut buf) {
-            Ok(()) => Ok(i8::try_from(buf[0]).expect("U8 overflow when reading register")),
+            Ok(()) => Ok(buf[0] as i8),
             Err(_) => Err(Bme680Error::CommunicationFailure),
         }
     }