Added Resources for Blockchain And Solidity (HacktoberFest) (#5973)

* Added free-programming-playgrounds for Solidity

* Added free-programming-interactive-tutorials-en for Solidity

* Update free-programming-interactive-tutorials-en.md

* Added free-programming-cheatsheets for Solidity

* Added free-courses-en for Blockchain

* Update free-courses-en.md

* Update free-courses-en.md

* Update free-courses-en.md

* Update free-programming-cheatsheets.md

* Update free-programming-cheatsheets.md

* Update free-programming-cheatsheets.md

* Update free-courses-en.md

* Update free-programming-playgrounds.md

* Update free-programming-cheatsheets.md

* Update free-programming-interactive-tutorials-en.md

* Update free-programming-playgrounds.md

* Recover deleted Manoj Ramesh resource

Co-authored-by: David Ordás <3125580+davorpa@users.noreply.github.com>

* Update more/free-programming-playgrounds.md

Co-authored-by: David Ordás <3125580+davorpa@users.noreply.github.com>

* add creator

Co-authored-by: David Ordás <3125580+davorpa@users.noreply.github.com>

Co-authored-by: Eric Hellman <eric@hellman.net>
Co-authored-by: David Ordás <3125580+davorpa@users.noreply.github.com>

courses/free-courses-en.md

@@ -64,6 +64,7 @@
 * [Rust](#rust)
 * [Scala](#scala)
 * [Security](#security)
+* [Solidity](#solidity)
 * [Swift](#swift)
   * [Vapor](#vapor)
 * [Theory](#theory)
@@ -810,6 +811,12 @@
 * [Zero to Hero: A Practical Network Penetration Testing Course](https://www.youtube.com/playlist?list=PLLKT__MCUeiwBa7d7F_vN1GUwz_2TmVQj) - The Cyber Mentor
 
 
+### Solidity
+
+* [Learn Solidity](https://youtube.com/playlist?list=PL16WqdAj66SCOdL6XIFbke-XQg2GW_Avg) - Will it Scale (Youtube)
+* [MASTER Solidity for Blockchain](https://youtube.com/playlist?list=PLS5SEs8ZftgVnWHv2_mkvJjn5HBOkde3g) - Dapp University (Youtube)
+
+
 ### Swift
 
 * [100 days of Swift](https://www.hackingwithswift.com/100) - Hacking With Swift