Bug fixes

Various improvements to the Delegate class template.
Memory footprint reduction of SoftwareSerial instances based on 3rd party contribution by @dirkmueller

6.5.4

Bump release for global consistency of Delegate.h in released libraries.

Parity bug fix

Overflow condition caused data and parity to get out of sync permanently.

6.5.2

Move logger setup to the front of setup() to allow early diagnostic o…

Multiple fixes

Must not yield (or optimistic_yield()) in critical section that blocks all interrupts. Affected was write(...).
Put functions used while interrupts are blocked into IRAM cache.
In repeater example, detect parity errors.
Don't display parity error report though with HW serial it's not computed.

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).

6.4.0: Reinstate "waveform" output generator.

Non-parity modes save 56 bytes of heap memory now.

6.3.0

Drop waveform-generating write code in favor of maintainable inverse …

6.2.2

Updated examples. Requires inverse logic support in ESP8266 HardwareS…

6.2.1

In loopback example, explicit pin settings and for ESP32, realistic m…