[MERGE] Make knits the default format

[Jamie Wilkinson]

This one time, at band camp, Robert Collins wrote:
>Again, theres more than 'just toggle the default' - because if there
>isn't, tests dont pass.
>
>Rob
>-- 
>GPG key available at: <http://www.robertcollins.net/keys.txt>.

>=== modified file 'a/NEWS'
>--- a/NEWS	
>+++ b/NEWS	
>@@ -78,9 +78,10 @@
>     * 'merge' accepts --remember option to store parent location, like 'push'
>       and 'pull'. (Olaf Conradi)
> 
>-    * 'Metadir' is now the default disk format. This improves behaviour in
>-      SFTP using circumstances and allows binding and rebinding and easier
>-      use of repositories. (Robert Collins, Aaron Bentley).
>+    * 'knit' is now the default disk format. This improves disk performance and
>+      utilization, increases incremental pull performance, robustness with SFTP
>+      and allows checkouts over SFTP to perform acceptable. 

Typo:

"to perform acceptably."