Add binaries and update download docs.

docs/content/1.tutorial/default.yml

@@ -1,7 +1,7 @@
 headline: Tutorial
 body:
   - text: |
-    
+
       Twitter have a JSON API, so let's play with that. This URL gets
       us the last 5 tweets about JSON:
       

docs/content/2.download/default.yml

@@ -7,13 +7,18 @@ body:
       possible to build it for nearly any platform. Prebuilt binaries are
       available for Linux (64-bit x86) and OS X.
     
-       * [Download binary for 64-bit Linux](/download/linux/x68_64/jq)
-       * [Download binary for OS X](/download/osx/64/jq)
+       * [Download binary for 64-bit Linux](/download/linux_x86_64/jq)
+       * [Download binary for OS X](/download/osx_64/jq)
        * [Download source](/download/source/jq.tgz)
 
+      The binaries should just run, but you may need to make them
+      executable first using:
+
+          chmod +x jq
+       
       jq is licensed under the MIT license. For all of the gory
       details, read the file `COPYING` in the source distribution.
-       
+
       Hacking on jq
       =============