Remove broken page (#2634)

Author deleted page partially.
He write message on the page: This book has been removed as it will shortly be published by APress.

free-programming-books.md

@@ -1170,7 +1170,6 @@
 * [Go for Javascript Developers](https://github.com/bulim/go-for-javascript-developers)
 * [Learning Go](https://miek.nl/go/)
 * [Let's learn Go!](http://go-book.readthedocs.io/en/latest/)
-* [Network programming with Go](https://jan.newmarch.name/go/)
 * [Practical Cryptography With Go](https://leanpub.com/gocrypto/read)
 * [The Go Tutorial](http://tour.golang.org)
 * [The Little Go Book](https://github.com/karlseguin/the-little-go-book)