cal_uart(with fifo) + NIOSserial.c

We were able to get the cal_uart working fully only after modifying the verilog code.

It seems that it only supports polling mode cleanly.

When using interrupts, it doesn't generate them in a way that takes advantage of the fifo's.

We had to modify our verilog code so that interrupts were generated only when the fifo was 75% full for example.

This was done by changing the "qualified_irq" assignment.

Until we made the modifications, the cal_uart component didn't perform any different than the normal Altera_Avalon_Uart.