hackndev/zinc — pull request #228 by kvark (2014-11-09 04:24:19+00:00)
Title: STM32L1 - USART and system clocks

This PR greatly expands stm32l1 board support with:
* foundation for USART logic
* new `app_usart_stm32l1` that sends "Hello, World!" to the virtual com (`/dev/ttyACM0`)
* solid part of the system clock configuration, including HSI, MSI, and partially PLL