fix image check in production bug

@@ -30,9 +30,9 @@ const stringProcess = require('./utils/string-process');
 const app = express();
 
 // 向模板注入变量
-app.locals.devEnv = app.get('env') === 'development';
-app.locals.isProduction = app.get('env') === 'production';
-app.locals.version = pkg.version;
+global.devEnv = app.locals.devEnv = app.get('env') === 'development';
+global.isProduction = app.locals.isProduction = app.get('env') === 'production';
+global.version = app.locals.version = pkg.version;
 app.locals.startTime = moment().format('YYYYMMDDHH');
 app.locals.currentYear = moment().format('YYYY');