Multiple fixes.

Fixes #129
Fixes #128
Subtle change in API contract: readBytes() are blocking in Stream and HardwareSerial. EspSoftwareSerial adopts this behavior now.
For non-blocking buffer read, use the new read(buffer, size) functions.
Fixes #127
Bump minor release tag.
Use millis() for timeout over cycles - prefer long blocking over performance because user has a choice.
Fixed repeater example after all this time.
Loopback example defaults to datarate that works over a real wire board to board (ESP8266, ESP32, mix).