Add example of new alarm setting method

src/lib.rs

@@ -421,6 +421,21 @@
 //! rtc.enable_alarm2_interrupts().unwrap();
 //! # }
 //! ```
+//!
+//! ### Set the Alarm1 to a specific time
+//!
+//! ```no_run
+//! extern crate ds323x;
+//! extern crate linux_embedded_hal as hal;
+//! use ds323x::{Ds323x, Hours, NaiveTime};
+//!
+//! # fn main() {
+//! let dev = hal::I2cdev::new("/dev/i2c-1").unwrap();
+//! let mut rtc = Ds323x::new_ds3231(dev);
+//! let time = NaiveTime::from_hms(19, 59, 58);
+//! rtc.set_alarm1_hms(time).unwrap();
+//! # }
+//! ```
 
 #![deny(unsafe_code, missing_docs)]
 #![no_std]