[PC-1103] - Nicla Voice User Manual (#1024)

* Initial commit

* Content update, graphics and files added

* Content update, powering the board

* Content update, NDP processor firmware update

* Content update, banner

* Gatsby error fix

* Gatsby error fix

* Gatsby error fix

* Content update, board architecture overview

* Content update, powering the board

* Content update, datasheet, schematics and STEP files

* Grammar check

* Content update, board pins

* Content update, board actuators

* Content update, board pins

* Content update, support

* Content update, BLE

* Content update, UART

* Content update, I2C

* Content update, SPI

* Content update

* Content update, microphone

* Spell check

* Linter fix

* Content update, microphone

* Content update, board core and libraries

Co-authored-by: martab1994 <93210545+martab1994@users.noreply.github.com>

* Content update, grammar

Co-authored-by: martab1994 <93210545+martab1994@users.noreply.github.com>

* Content update, typo

Co-authored-by: martab1994 <93210545+martab1994@users.noreply.github.com>

* Content update, titles

* Content update, grammar

Co-authored-by: martab1994 <93210545+martab1994@users.noreply.github.com>

* Content update, grammar

Co-authored-by: martab1994 <93210545+martab1994@users.noreply.github.com>

* Content update, grammar

* Content update, Julian's review

* Content update, single point links

* Files not used deleted

* Content update, single point links

* Content update, grammar

Co-authored-by: Julián Caro Linares <jcarolinares@gmail.com>

* Content update, analog pins

Co-authored-by: Julián Caro Linares <jcarolinares@gmail.com>

* Content update, spelling

Co-authored-by: Julián Caro Linares <jcarolinares@gmail.com>

* Content update, digital pins

* Content update, tutorial link fix

* Content update, IMU and magnetometer

* Content update, Julian's second review

* Content update, application notes section added

* Content update, Julian and Marta's last review

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Co-authored-by: José Antonio Bagur Nájera <josea.bagur@gmail.com>
Co-authored-by: martab1994 <93210545+martab1994@users.noreply.github.com>
Co-authored-by: Julián Caro Linares <jcarolinares@gmail.com>

Author: 4 people