Remove legacy changes for double buffered SPI
Eliminate unecessary ESP32 SPI read/modify write
Eliminate two stage control bit changes (may impact some diplays with
setup/hold timing and show ESP32 hardware register bug?)
Add single register write for CS and DC command
Make setAddrWindow smarter (as used in previous AVR library)
Improve compatibility with GFX sketches
Re-arrange comments slightly to improve positioning