Added

• Added rcc::Lsco to use the low-speed oscillator output.
• Added Rtc::calibrate_lp to calibrate the RTC.
• Added Rtc::recalibration_pending.
• Added Rtc::is_alarm_{a,b}_en.
• Added methods to utilize ADC oversampling.

Changed

• Rtc.alarm_{a,b} returns Alarm instead of Option<Alarm>.
• Updated stm32-rs from 0.14.0 to 0.15.1.

Fixed

• Fixed a documentation bug in rtc::Alarm. Values are masked if true, but the documentation indicated they are masked if false.