add option to reset after send

[eteq]

Just what it says on the tin!

Note this is probably not super-robust as it depends on "ctrl-c" followed by "ctrl-d" being an effective reset code. It seems to work well at least on the ESP32 micropython 1.14 I'm testing on though...

[IhorNehrutsa]

Also tested on ESP32 micropython 1.13

[IhorNehrutsa]

Also tested on ESP32 micropython 1.15

[bulletmark]

Does this work reliably for you guys? It barely works for me. Works better if I add some small time delays between the send() calls. Note that webrepl file get and send, and the terminal all work fine.