add option to exit after make_help + fix exit code

- Defaults to previous behaviour, which was to exit.
- Fix the returned exit code: was 1, but should be 0, as asking for help
is not an error.

eo/src/utils/checkpointing

@@ -47,7 +47,7 @@
 #include "eoGenCounter.h"
 
 // and make_help - any better suggestion to include it?
-void make_help(eoParser & _parser);
+void make_help(eoParser & _parser, bool exit_after = true);
 
 #endif // !_CHECKPOINTING_
 

eo/src/utils/make_help.cpp

@@ -44,7 +44,7 @@ using namespace std;
  * It is declared in all make_xxx.h files in representation-dependent dirs
  * but it is NOT representation-dependent itself - that's why it's in utils
  */
-void make_help(eoParser & _parser)
+void make_help(eoParser & _parser, bool exit_after)
 {
     // name of the "status" file where all actual parameter values will be saved
     string str_status = _parser.ProgramName() + ".status"; // default value
@@ -65,7 +65,9 @@ void make_help(eoParser & _parser)
         _parser.printHelp(cout);
         cout << "You can use an edited copy of file " << statusParam.value()
              << " as parameter file" << endl;
-        exit(1);
+        if(exit_after) {
+            exit(0);
+        }
       }
 }