doc: add C? Go? Cgo! article

Originally published on The Go Programming Language Blog, March 17, 2011.

http://blog.golang.org/2011/03/c-go-cgo.html

Update #2547.

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/5777054
diff --git a/doc/progs/run b/doc/progs/run
index 9d4669b..8b383e59 100755
--- a/doc/progs/run
+++ b/doc/progs/run
@@ -28,7 +28,14 @@
 	interface2
 "
 
-all=$(echo $defer_panic_recover $effective_go $error_handling $law_of_reflection slices go1)
+c_go_cgo="
+    cgo1
+    cgo2
+    cgo3
+    cgo4
+"
+
+all=$(echo $defer_panic_recover $effective_go $error_handling $law_of_reflection $c_go_cgo slices go1)
 
 for i in $all; do
 	go build $i.go