Import Base project

Project file created with Atmel Studio 6.2 including the following Atmel
Software Framework components:
Generic board support
NVM - Non-volatile Memory Common API
EXTINT - External Interrupt
SERCOM USART - Serial Communications
SYSTEM - Core System Driver
Standard serial I/O (stdio)
FreeRTOS mini Real-Time Kernel 8.0.1
AVR2025 - IEEE 802.15.4 MAC v3.1.1