Make svnmucc's help message and option parsing a very little bit more similar
to that of the other command-line programs.

* subversion/svnmucc/svnmucc.c
  (usage): New function.
  (help): New name for old function 'usage'. Add 'and RA modules' to the
    description of '--version'.
  (sub_main): For an option parsing failure (unrecognized option) display a
    more 'friendly' error message by using the new 'usage' function. Don't
    execute the '--version' request until all options have been parsed, so
    unrecognized options (for example 'svnlook --version -q' currently) are
    reported even when appearing after the '--version' argument. Track the
    rename.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1625507 13f79535-47bb-0310-9956-ffa450edef68