Updating FakeTLS ClientHello to match modern desktop/android clients

[markpash]

Description

Currently the FakeTLS implementation in gotd/td is adequate and works with mtproto proxies. But the code that generates the ClientHello is missing a lot from the Desktop and Android implementations, and seems out of date. Since this is essentially an obfuscation and censorship evasion scheme, it seems appropriate to follow the other clients in their implementation. Given that the code is mostly a translation of the C++ code, updating it following the same scheme isn't difficult and I have partially done it locally.

Would the project be open to me contributing this?