Added new class MspAdc to read and calculate calibrated ADC readings when using the chip's internal voltage reference.
Cleaned up the implementation of the VCC_TYPE == VCC case so that the code is easier to follow. Previously, misleading names for the voltage reference and input channel were used. The actual implementation is the same and has no impact on the Vcc measurements of existing code.
Full Changelog: v1.2.1...v1.3.0