Fix many spelling errors and word repetitions (#188)

Many of the errors fixed in this commit are word repetitions
such as 'the the' and minor spelling errors. One formatting
error in the ksh man page has also been fixed.

src/cmd/ksh93/sh/fault.c

@@ -610,7 +610,7 @@ void sh_done(void *ptr, register int sig)
 		(*shp->userinit)(shp, -1);
 	if(t=shp->st.trapcom[0])
 	{
-		shp->st.trapcom[0]=0; /*should free but not long */
+		shp->st.trapcom[0]=0; /* should free but not long */
 		sh_trap(t,0);
 		savxit = shp->exitval;
 	}

src/cmd/ksh93/sh/macro.c

@@ -1072,7 +1072,7 @@ static char *nextname(Mac_t *mp,const char *prefix, int len)
 }
 
 /*
- * This routine handles $param,  ${parm}, and ${param op word}
+ * This routine handles $param, ${param}, and ${param op word}
  * The input stream is assumed to be a string
  */
 static int varsub(Mac_t *mp)

src/cmd/ksh93/sh/name.c

@@ -1115,7 +1115,7 @@ Namval_t *nv_create(const char *name,  Dt_t *root, int flags, Namfun_t *dp)
 					else if(n==0 && (c==0 || (c=='[' && !nv_isarray(np))))
 #endif /* SHOPT_FIXEDARRAY */
 					{
-						/* subscript must be 0*/
+						/* subscript must be 0 */
 						cp[-1] = 0;
 						n = sh_arith(shp,sp+1);
 						cp[-1] = ']';

src/cmd/ksh93/sh/subshell.c

@@ -787,7 +787,7 @@ Sfio_t *sh_subshell(Shell_t *shp,Shnode_t *t, volatile int flags, int comsub)
 			/* Detach this scope from the unified view. */
 			shp->track_tree = dtview(sp->strack,0);
 			/* Delete (free) all elements of the subshell hash table. To allow dtnext() to
-			   set the pointer to the next item, we have to delete one item beind the loop. */
+			   set the pointer to the next item, we have to delete one item behind the loop. */
 			prev_np = 0;
 			np = (Namval_t*)dtfirst(sp->strack);
 			while(np)