Add OpenID to CodiMD

With OpenID every OpenID capable provider can provide authentication for
users of a CodiMD instance. This means we have federated
authentication.

Signed-off-by: Sheogorath <sheogorath@shivering-isles.com>

lib/response.js

@@ -88,6 +88,7 @@ function showIndex (req, res, next) {
     email: config.isEmailEnable,
     allowEmailRegister: config.allowEmailRegister,
     allowPDFExport: config.allowPDFExport,
+    openID: config.isOpenIDEnable,
     signin: authStatus,
     infoMessage: req.flash('info'),
     errorMessage: req.flash('error'),
@@ -142,7 +143,8 @@ function responseCodiMD (res, note) {
     oauth2: config.isOAuth2Enable,
     email: config.isEmailEnable,
     allowEmailRegister: config.allowEmailRegister,
-    allowPDFExport: config.allowPDFExport
+    allowPDFExport: config.allowPDFExport,
+    openID: config.isOpenIDEnable
   })
 }