Inline yieldFromTick() with plain cut and paste

	modified:   port.c
Cleanup port.c - use 24_BIT variable

	modified:   port.c
First commit

Minimal working code.
New USART Driver

+ Usart driver
+ USART Loopback example
Update readme
Repository maintenance
Proper clock setup

Proper clock setup using sysclk.
+ TWI (I2C) task
gitignore update