Feature requests send tx string on boot

[rraat]

As we all know the esp sends out garbage at boot time on the TX line. For an Esp01 we can't flip the controll/data lines as these are not available on the 8 pin pin header. I have a Nas attached to an esp and Uboot stops because of "key pressed" I can continue booting by entering "boot\n" on the console

Would be great if we could sent a configurable string over serial when esplink boots? Guess there would be many more cases where this would be practical to resume from a power outage