Serial Blocks Would Benefit from "Flush"

[JonMcPhalen]

Those of us who code in Spin or C via SimpleIDE have access to flush methods when using a serial cog. Unfortunately, this doesn't exist in BlocklyProp.

I would like to propose a [Serial RX Flush] block that is translated to
fdserial_rxFlush (fdserial *term)

...and a [Serial TX Flush] block that is translated to
fdserial_txFlush (fdserial *term)

On a recent project for Ken (TFmini-S demo) I really needed RF Flush to I coded it as a custom block. This works, but the custom block has to be edited if the pin assignments for the serial connection get changed.