Added workaround for I2C pins on LPC11xx, LPC13xx.
Added mode control for I2C pins on LPC17xx.
Refactored ADC classes.
ADC subsystem divided into separate modules: AdcUnit, simple Adc class
with polling and interrupt-based AdcBurst class.
Fixed ADC conversions with software start.
Minor updates in buffer types of ADC classes.
Minor updates in DAC classes and definitions.
Added SerialPoll interface.
SerialPoll is a lightweight serial interface without interrupts or DMA.
Added power management for SerialDma interface.