Fix a few minor issues (#473)

Changes:
- Fixed two xtrace test failures introduced in commit cfc8744c.
- The definition of _use_ntfork_tcpgrp in xec.c is now dependent on
  SHOPT_SPAWN being defined (re: 8e9ed5be).
- Removed many unnecessary newlines and fixed various typos.

src/cmd/ksh93/edit/edit.c

@@ -69,7 +69,6 @@ static Lex_t *savelex;
     {
 	switch(c)
 	{
-	    
 	    case cntl('A'): return('A');
 	    case cntl('B'): return('B');
 	    case cntl('C'): return('C');