Add configuration exporting

The runtime configuration of a MaxScale can now be exported to a single
file. This allows modifications made via runtime configuration commands to
be "committed" for later use.

server/core/internal/config.h

@@ -44,6 +44,16 @@ extern const char *config_monitor_params[];
 extern const char *config_filter_params[];
 extern const char *config_server_params[];
 
+/**
+ * Initialize the configuration subsystem
+ */
+void config_init();
+
+/**
+ * Finalize the configuration subsystem
+ */
+void config_finish();
+
 /**
  * Set the defaults for the global configuration options
  */
@@ -163,4 +173,13 @@ void fix_section_name(char *section);
  */
 bool config_global_serialize();
 
+/**
+ * Export the configuration to a file
+ *
+ * @param filename Filename where the configuration will be written
+ *
+ * @return True if configuration was successfully exported
+ */
+bool export_config_file(const char* filename);
+
 MXS_END_DECLS