remove nacl

The recent linker changes broke NaCl support
a month ago, and there are no known users of it.

The NaCl code can always be recovered from the
repository history.

R=adg, r
CC=golang-dev
https://golang.org/cl/3671042
diff --git a/doc/install.html b/doc/install.html
index 8df3d42..92b099f 100644
--- a/doc/install.html
+++ b/doc/install.html
@@ -62,7 +62,7 @@
 </p>
 
 <p>
-The compilers can target the FreeBSD, Linux, Native Client,
+The compilers can target the FreeBSD, Linux,
 and OS X (a.k.a. Darwin) operating systems.
 (A port to Microsoft Windows is in progress but incomplete.  See the 
 <a href="http://code.google.com/p/go/wiki/WindowsPort">Windows Port</a>
@@ -340,7 +340,6 @@
 	Choices for <code>$GOOS</code> are <code>linux</code>,
 	<code>freebsd</code>,
 	<code>darwin</code> (Mac OS X 10.5 or 10.6),
-	<code>nacl</code> (Native Client, an incomplete port),
 	and <code>windows</code> (Windows, an incomplete port).
 	Choices for <code>$GOARCH</code> are <code>amd64</code> (64-bit x86, the most mature port),
 	<code>386</code> (32-bit x86), and
@@ -372,9 +371,6 @@
 	<td></td><td><code>linux</code></td> <td><code>arm</code></td> <td><i>incomplete</i></td>
 	</tr>
 	<tr>
-	<td></td><td><code>nacl</code></td> <td><code>386</code></td>
-	</tr>
-	<tr>
 	<td></td><td><code>windows</code></td> <td><code>386</code></td> <td><i>incomplete</i></td>
 	</tr>
 	</table>