Adds option to use generated AP name but with password

[javl]

This update allows you to use a generated AP name, but also set a password.
wifiManager.ssidFromId() returns the generated AP name, so you can use it in the original autoConnect() functions:

// use generated AP name, no password (as before)
wifiManager.autoConnect();
// Use a generated AP name, but also a password
wifiManager.autoConnect(wifiManager.ssidFromId(), "AP-PASSWORD");

[javl]

Closing this pull request as I need to test it first; resulted in a weird AP name