National Geographic RSS support (#389)

* National Geographic RSS

* fix format warning

* docs

* full text by default && correct docs

* format fix ci check

* correct docs

router.js

@@ -342,6 +342,9 @@ router.get('/pku/eecs/:type?', require('./routes/pku/eecs'));
 // 机核
 router.get('/gcores/category/:category', require('./routes/gcores/category'));
 
+// 国家地理 National Geographic
+router.get('/natgeo/:cat/:type?', require('./routes/natgeo/natgeo'));
+
 // 一个
 router.get('/one', require('./routes/one/index'));