adding the book Data Centric Intro to Computation (#6886)

* adding the book Data Centric Intro to Computation

* removed / that linter wanted me to remove

books/free-programming-books-subjects.md

@@ -210,6 +210,7 @@ Books that cover a specific programming language can be found in the  [BY PROGRA
 
 ### Computer Science
 
+* [A Data-Centric Introduction to Computing](https://dcic-world.org) - Kathi Fisler, Shriram Krishnamurthi, Benjamin S. Lerner, Joe Gibbs Politz (HTML)
 * [Computational Thinking](https://www.cs.cmu.edu/~15110-s13/Wing06-ct.pdf) - Jeannette Wing, Carnegie-Mellon University (PDF)
 * [Computer Science I - Draft](https://bitbucket.org/chrisbourke/computersciencei/src) - Dr. Chris Bourke (PDF) (:construction: *in process*)
 * [Computer Science II - Draft](http://cse.unl.edu/~cbourke/ComputerScienceTwo.pdf) - Dr. Chris Bourke (PDF) (:construction: *in process*)