add a paragraph in the FAQ about the situation with Windows support

R=rsc, iant
CC=golang-dev
https://golang.org/cl/154059

doc/go_faq.html

@@ -78,6 +78,18 @@ lack of concurrency awareness—are rooted in the design of
 the C and C++ languages themselves.
 We felt a viable solution required a more complete approach.
 
+<h3 id="Why_doesnt_Go_run_on_Windows">
+Why doesn't Go run on Windows?</h3>
+
+<p>
+We understand that a significant fraction of computers in the world
+run Windows and it would be great if those computers could run Go
+programs. However, the Go team is small and we don't have the
+resources to do a Windows port at the moment.  We would be
+more than willing to answer questions and offer advice to anyone
+willing to develop a Windows version.
+</p>
+
 <h2 id="Usage">Usage</h2>
 
 <h3 id="Who_should_use_the_language">