add get_exec_path from Workflow

src/jflow/workflow.py

@@ -178,6 +178,9 @@ class Workflow(threading.Thread):
                 parameters[param.group] = [param]
         return [parameters, parameters_order]
     
+    def get_exec_path(self, software):
+        return self.jflow_config_reader.get_exec(software)
+    
     def add_component(self, component_name, args=[], kwargs={}, component_prefix="default"):
         # first build and check if this component is OK
         if self.comp_pckg.has_key(component_name):