Merge pull request #1035 from Mouseion/patch-interactive

Update interactive tutorials

free-programming-interactive-tutorials-en.md

@@ -35,6 +35,7 @@
 
 
 ###Go
+* [Go Koans](https://github.com/cdarwin/go-koans)
 * [The Go Tutorial](http://golang.org/doc/go_tutorial.html)
 
 
@@ -87,6 +88,7 @@
 
 
 ###PHP
+* [CodeCademy PHP](http://www.codecademy.com/tracks/php)
 * [Learn PHP](http://www.learn-php.org/)