show github login button

lib/util/swigFunctions.js

@@ -97,6 +97,11 @@ module.exports = function(crowi, app, req, locals) {
     return locals.isEnabledPassport() && config.crowi['security:passport-google:isEnabled'];
   };
 
+  locals.passportGitHubLoginEnabled = function() {
+    var config = crowi.getConfig();
+    return locals.isEnabledPassport() && config.crowi['security:passport-github:isEnabled'];
+  };
+
   locals.searchConfigured = function() {
     if (crowi.getSearcher()) {
       return true;