First version of the library documentation (#7)

This PR contains the work done to write the main article of the `DocC` documentation for the library, which introduces the library as well as explains how to install it and use it.

Reviewed-on: #7
Co-authored-by: Javier Cicchelli <javier@rock-n-code.com>
Co-committed-by: Javier Cicchelli <javier@rock-n-code.com>

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+
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