Issue 78 in svnbook: A fuller explanation of '--depth ARG' in section 'svn Options' would be useful

[svnbook at googlecode.com]

Comment #1 on issue 78 by chr... at lavabit.com: A fuller explanation  
of '--depth ARG' in section 'svn Options' would be useful
http://code.google.com/p/svnbook/issues/detail?id=78

Additional:
	svn: --depth and --set-depth are mutually exclusive.
This appears nowhere in the book.

The `--set-depth ARG` option also supports the 'exclude' argument.
This is also not mentioned in the book.

 From svn_types.h:
   /* Exclude (i.e., don't descend into) directory D. */
   svn_depth_exclude    = -1,