Add new Blockchain book (#6871)

* Added French Book Maitriser Ethereum

* Added English book Mastering the Lightning Network

* Added French Book + link correction

* Revert "Added English book Mastering the Lightning Network"

This reverts commit 9613319.

* Added English book

* redressing the french URLs

* added "Learning Bitcoin from the Command Line"

* Update books/free-programming-books-subjects.md

Co-authored-by: ImVector <[email protected]>

Co-authored-by: ImVector <[email protected]>

Author: SerafDosSantos

Diff for: books/free-programming-books-subjects.md

@@ -145,6 +145,7 @@ Books that cover a specific programming language can be found in the  [BY PROGRA
 * [Getting Started with Enterprise Blockchain: A Guide to Design and Development](https://www.ibm.com/downloads/cas/RYWXAR0M) - Michael Bradley, David Gorman, Matt Lucas, Matthew Golby-Kirk (PDF)
 * [Grokking Bitcoin](https://rosenbaum.se/book/) - Kalle Rosenbaum (HTML)
 * [IBM Blockchain: The Founder’s Handbook, Third Edition](https://www.ibm.com/downloads/cas/GZPPMWM5) - Antonio Banda, Matthew Hamilton, Eileen Lowry, John Widdifield et al. (PDF)
+* [Learning Bitcoin from the Command Line](https://github.com/BlockchainCommons/Learning-Bitcoin-from-the-Command-Line) - Christopher Allen, Shannon Appelcline et al. (HTML)
 * [Mastering Bitcoin - Unlocking digital currencies (2017), 2nd Edition](https://github.com/bitcoinbook/bitcoinbook) - Andreas M. Antonopoulos (AsciiDoc)
 * [Mastering Ethereum (2018), 1st Edition](https://github.com/ethereumbook/ethereumbook) - Andreas M. Antonopoulos, Gavin Wood (AsciiDoc)
 * [Mastering the Lightning Network](https://github.com/lnbook/lnbook) - Andreas M. Antonopoulos, Olaoluwa Osuntokun, Rene Pickhardt (AsciiDoc)