Argument Parsing

- Obsoleted Command::exectute  'commandLine' argument.  It is worse
  than unnecessary, it is an uncategorized raw argument string, which
  is only really useful for the 'execute' command, which itself now
  calls Arguments::combine to reconstruct the command line string.

src/commands/CmdSummary.cpp

@@ -50,7 +50,7 @@ CmdSummary::CmdSummary ()
 // Project  Remaining  Avg Age  Complete  0%                  100%
 // A               12      13d       55%  XXXXXXXXXXXXX-----------
 // B              109   3d 12h       10%  XXX---------------------
-int CmdSummary::execute (const std::string&, std::string& output)
+int CmdSummary::execute (std::string& output)
 {
   int rc = 0;