stabilize path names in html output

[Olaf Hering]

 On Wed, May 18, Max Bowsher wrote:

> Sorry, but this is a really nasty hack. If we wanted to do any build time 
> substitutions, then the correct way to do it would be with XML entities, as 
> is currently done to substitute the revision number into the title page of 
> the book.

Ok, I will have a look at this option.
> 
> However, the book is a general piece of information not necessarily 
> customized for any particular Subversion installation, so I do not think 
> customized substitutions are required.

I build the svnbook from source and put svn-book.html into our
subversion-doc package.

> There are already several different preferences for a system repository 
> base path, and of course repositories can actually go anywhere at all, so I 
> think it's fine just to use one in the book, and let people apply their 
> personal preferences to their own systems.

Sure, the desired values can be overridden via make options.

> Regarding binary paths, I suggest just using "/usr/bin/" everywhere - 
> anyone who custom-installs Subversion somewhere else will easily understand 
> the change they need to make to examples.

I can prepare such a patch, if XML entities are not wanted.