WIP GPIO Section improvements for the User Experience of most of the …

[jcarolinares]

…users

What This PR Changes

• GPIO Section improvements for the User Experience of most of the users

The idea is:

1- What are we going to explain 2- Global Table 3- Linux 4- Arduino 5 - Deep explanation about how GPIOs work inside the STM32 and how those pins were calculated

Check TODO tags

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