Fix documentation and comments for buffer optimizations in example

Also, swsertest has received a #define that showcases how switching the HW serial to GPIOs and using EspSoftwareSerial for logging instead can be accomplished.

Delegate: field padding improved for code size and performance

6.11.4

Field padding improved

Prepares for ESP8266 Arduino core PR 6979.

6.11.3

Fixes #171: prepares for ESP8266 Arduino core PR 6979.

EspSoftwareSerial 6.11.2

Delegate<> assign operators added.
Addresses compilation errors with pending PRs to ESP8266 Arduino Core.

6.11.1

Fix unused parameter warning.

More GPIOs for ESP32

6.11.0

Bump minor version

EspSoftwareSerial bug fix release 6.10.1

preciseDelay() could delay() for extremely long time, if period duration was exceeded on entry.

6.10.0

Aligning to ESP8266 Arduino core, there: "BREAKING: Add Print::availableForWrite method (#7658)"

According to https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-reference/peripherals/gpio.html,
GPIOs from 36 to 39 can be utilized for output on ESP32-S2, but there are issues with IRQ and internal pullups. Hence, GPIOs 34 and 35 must
be set to blocked for Rx to avoid conflicting use of the input w/ pullup mode that's used.
Inspired by, half-way fixes plerup#182

6.9.0

Bump minor version due to small change in yield behavior.

6.8.5

On ESP8266, HW serial announces parity errors as general rx errors. R…