modify 'Github' -> 'GitHub'

lib/routes/admin.js

@@ -137,8 +137,8 @@ module.exports = function(crowi, app) {
     settingForm = Config.setupCofigFormData('crowi', req.config);
 
     const highlightJsCssSelectorOptions = {
-      'github':           { name: '[Light] Github',         border: false },
-      'github-gist':      { name: '[Light] Github Gist',    border: true },
+      'github':           { name: '[Light] GitHub',         border: false },
+      'github-gist':      { name: '[Light] GitHub Gist',    border: true },
       'atom-one-light':   { name: '[Light] Atom One Light', border: true },
       'xcode':            { name: '[Light] Xcode',          border: true },
       'vs':               { name: '[Light] Vs',             border: true },