message catalogs: fix comment lines, also remove linux hack in merge.c

According to the spec, blank lines in message catalogs or lines
beginning with '$ ' are valid comments.

However, there were many cases where lines in the message catalogs
contained just a single '$', without the required space after it.

Under linux, this caused 126766 error lines (in my builds) of the
form:

... unknown directive `': line ignored

This also causes gencat to exit with a non-0 exit code.  Even though
gencat says it ignores the line, it really doesn't.

An early porting change to programs/localized/util/merge.c was made to
ignore this return value on linux.  This hack has now been removed.

Build logs are a lot smaller and cleaner now.

cde/programs/dtprintegrate/dtlp.msg

@@ -42,9 +42,9 @@ $ *************************************<L>*************************************
 $quote "
 
 $set 1
-$
+$ 
 $  -- The first group of messages all appear on the Print dialog --
-$
+$ 
 
 
 $  This is the message that appears in the "Printer Name:" field when no
@@ -89,9 +89,9 @@ $  This is the label on the right button. Pushing this button causes a
 $  help dialog to be posted.
 120 "Help"
 
-$
+$ 
 $  -- The following are error messages. --
-$
+$ 
 
 $  This message is posted when there is a problem with the file specified. 
 $  The file name will be appended to the message. One additional message
@@ -114,9 +114,9 @@ $  in setting up to print.
 $  This is the label that appears in the title bar of the error dialog.
 160 "Print Information"
 
-$
+$ 
 $  -- Strings used in the Print dialog and Select Printer dialog in CDEnext --
-$
+$ 
 $  This is the label for the field indicating the file(s) that will be printed.
 170 "File Name(s): "
 
@@ -130,9 +130,9 @@ $  This is the label for the printer list in the Select Printer dialog.
 $  This is the label for the text box in the Select Printer dialog.
 200 "Printer Information:"
 
-$
+$ 
 $  -- The following are error messages added for CDEnext --
-$
+$ 
 $  File is not printable or does not exist.
 210 "That file is either not printable or it does not exist."