Revision 1845637

Merge the r1842814 group from trunk:

 * r1842814, r1842827, r1842829, r1842877
   Improve 'svn help' for the 'add' command and for the '-N' option.
   Justification:
     Proper documentation was lacking. Another newbie was recently surprised
     by how 'svn add' behaves relative to 'git add'.
   Notes:
     r1842814: Document the obsolete '-N' option properly.
     r1842827: Fully document 'svn add', and include some newbie tips.
     r1842829, r1842877: tweaks to formatting.
   Votes:
     +1: julianfoad, stsp, brane