Made ~ a non-breaking space character at start of strings - useful for keeping...

Made ~ a non-breaking space character at start of strings - useful for keeping help message next to option names.  For example: to get "-thresh <value>      binary threshold" you put in "~<value>\tbinary threshold" as the help text

functions.cc

@@ -96,9 +96,13 @@ namespace Utilities {
   }
 
   ostream& operator<<(ostream &os, const BaseOption& o) {
-    return os << 
-      "\t" << o.key() << 
-      "\t" << o.help_text();
+    string test=o.help_text();
+    if ((test.length()>=1) && (test[0]=='~')) {
+      test[0]=' ';
+      return os << "\t" << o.key() << test;
+    } else {
+      return os << "\t" << o.key() << "\t" << o.help_text();
+    }
   }
 
 }