Specifiy function param types in docs

docs/api/app.md

@@ -193,6 +193,7 @@ Returns:
   * `validExpiry` Integer - End date of the certificate being valid in seconds
   * `fingerprint` String - Fingerprint of the certificate
 * `callback` Function
+  * `isTrusted` Boolean - Whether to consider the certificate as trusted
 
 Emitted when failed to verify the `certificate` for `url`, to trust the
 certificate you should prevent the default behavior with
@@ -221,6 +222,7 @@ Returns:
 * `url` URL
 * `certificateList` [Certificate[]](structures/certificate.md)
 * `callback` Function
+  * `certificate` [Certificate](structures/certificate.md)
 
 Emitted when a client certificate is requested.
 
@@ -255,6 +257,8 @@ Returns:
   * `port` Integer
   * `realm` String
 * `callback` Function
+  * `username` String
+  * `password` String
 
 Emitted when `webContents` wants to do basic auth.
 
@@ -696,6 +700,8 @@ app.setJumpList([
 ### `app.makeSingleInstance(callback)`
 
 * `callback` Function
+  * `argv` String[] - An array of the second instance's command line arguments
+  * `workingDirectory` String - The second instance's working directory
 
 This method makes your application a Single Instance Application - instead of
 allowing multiple instances of your app to run, this will ensure that only a