[MERGE] Trivial User Guide fixes

[Ian Clatworthy]

Matthew D. Fuller wrote:
> On Thu, Mar 27, 2008 at 12:04:40PM +1100 I heard the voice of
> Robert Collins, and lo! it spake thus:
>> I would say that 
>> bzr revert -r -2
>> is a more natural thing here.
> 
> Hm.  True, as a user.  I think it's slightly less clear as the
> example.  Maybe we should add a "In practice, you might instead write
> this as [...]"?
> 
> 
bb:tweak

I'll add the text above when I merge it.

Ian C.