Add option modules_enabled_by_default

SConstruct

@@ -137,6 +137,7 @@ opts.Add("extra_suffix", "Custom extra suffix added to the base filename of all
 opts.Add(BoolVariable("vsproj", "Generate a Visual Studio solution", False))
 opts.Add(BoolVariable("disable_3d", "Disable 3D nodes for a smaller executable", False))
 opts.Add(BoolVariable("disable_advanced_gui", "Disable advanced GUI nodes and behaviors", False))
+opts.Add(BoolVariable("modules_enabled_by_default", "If no, disable all modules except ones explicitly enabled", True))
 opts.Add(BoolVariable("no_editor_splash", "Don't use the custom splash screen for the editor", False))
 opts.Add("system_certs_path", "Use this path as SSL certificates default for editor (for package maintainers)", "")
 opts.Add(BoolVariable("use_precise_math_checks", "Math checks use very precise epsilon (debug option)", False))
@@ -259,7 +260,9 @@ for path in module_search_paths:
 
 # Add module options.
 for name, path in modules_detected.items():
+    if env_base["modules_enabled_by_default"]:
         enabled = True
+
         sys.path.insert(0, path)
         import config
 
@@ -269,6 +272,9 @@ for name, path in modules_detected.items():
             pass
         sys.path.remove(path)
         sys.modules.pop("config")
+    else:
+        enabled = False
+
     opts.Add(BoolVariable("module_" + name + "_enabled", "Enable module '%s'" % (name,), enabled))
 
 methods.write_modules(modules_detected)

main/main.cpp

@@ -375,8 +375,8 @@ void Main::print_help(const char *p_binary) {
 #ifdef TESTS_ENABLED
 	OS::get_singleton()->print("  --test [--help]                              Run unit tests. Use --test --help for more information.\n");
 #endif
-	OS::get_singleton()->print("\n");
 #endif
+	OS::get_singleton()->print("\n");
 }
 
 #ifdef TESTS_ENABLED