introduce ifc with FIFOs

app/src/async_ifc.py

@@ -0,0 +1,11 @@
+if __name__ == "app.src.async_ifc":
+    from app.src.byte_fifo import ByteFifo
+else:  # pragma: no cover
+    from byte_fifo import ByteFifo
+
+
+class AsyncIfc():
+    def __init__(self):
+        self.read = ByteFifo()
+        self.write = ByteFifo()
+        self.forward = ByteFifo()