* In Crypto.php or aes256.php, choose which of the ige implementation to use and complete it (4).
* In Session.php and TL, manage rpc errors, notifications, error codes and basically everything that isn't a normal response (4).
* In Connection.php and Session.php, add support for http, https and (maybe) udp connections and fix tcp intermediate connections (3).
* In API.php, complete a decent authorization flow that supports both bots and normal users (2).
* In PrimeModule.php, fix the mess in it, choose one of (the fastest) native php prime factorization function and implement it without biginteger (1.5).