adjust writeFast docs

[2bndy5]

Also amends an outdated comment in the definition.

New doc output:

Related to user experience described in #865

[github-actions]

Memory usage change @ e8b4fc6

Board	flash	%	RAM for global variables	%
ATTinyCore:avr:attinyx5	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:avr:nano	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:samd:mkrzero	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0

Click for full report table

Board	examples/rf24_ATTiny/rf24ping85 flash	%	examples/rf24_ATTiny/rf24ping85 RAM for global variables	%	examples/rf24_ATTiny/timingSearch3pin flash	%	examples/rf24_ATTiny/timingSearch3pin RAM for global variables	%	examples/GettingStarted flash	%	examples/GettingStarted RAM for global variables	%	examples/AcknowledgementPayloads flash	%	examples/AcknowledgementPayloads RAM for global variables	%	examples/ManualAcknowledgements flash	%	examples/ManualAcknowledgements RAM for global variables	%	examples/StreamingData flash	%	examples/StreamingData RAM for global variables	%	examples/MulticeiverDemo flash	%	examples/MulticeiverDemo RAM for global variables	%	examples/InterruptConfigure flash	%	examples/InterruptConfigure RAM for global variables	%	examples/scanner flash	%	examples/scanner RAM for global variables	%	examples/encodeRadioDetails flash	%	examples/encodeRadioDetails RAM for global variables	%
ATTinyCore:avr:attinyx5	0	0.0	0	0.0	0	0.0	0	0.0
arduino:avr:nano									0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0
arduino:samd:mkrzero									0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0

Click for full report CSV

Board,examples/rf24_ATTiny/rf24ping85<br>flash,%,examples/rf24_ATTiny/rf24ping85<br>RAM for global variables,%,examples/rf24_ATTiny/timingSearch3pin<br>flash,%,examples/rf24_ATTiny/timingSearch3pin<br>RAM for global variables,%,examples/GettingStarted<br>flash,%,examples/GettingStarted<br>RAM for global variables,%,examples/AcknowledgementPayloads<br>flash,%,examples/AcknowledgementPayloads<br>RAM for global variables,%,examples/ManualAcknowledgements<br>flash,%,examples/ManualAcknowledgements<br>RAM for global variables,%,examples/StreamingData<br>flash,%,examples/StreamingData<br>RAM for global variables,%,examples/MulticeiverDemo<br>flash,%,examples/MulticeiverDemo<br>RAM for global variables,%,examples/InterruptConfigure<br>flash,%,examples/InterruptConfigure<br>RAM for global variables,%,examples/scanner<br>flash,%,examples/scanner<br>RAM for global variables,%,examples/encodeRadioDetails<br>flash,%,examples/encodeRadioDetails<br>RAM for global variables,%
ATTinyCore:avr:attinyx5,0,0.0,0,0.0,0,0.0,0,0.0
arduino:avr:nano,,,,,,,,,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0
arduino:samd:mkrzero,,,,,,,,,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0

[2bndy5]

Also, see the rendered output at RTD for this PR: https://rf24--866.org.readthedocs.build/en/866/classRF24.html#_CPPv4N4RF249writeFastEPKv7uint8_t