Fix reconnecting the client

[vladbat00]

This PR actually fixes #334 (even though it was closed by the author) so that users won't need to employ the hacks by manually reconnecting the client.

Currently, the library handles reconnecting just fine, but only once. As we forget to set userDisconnected to false after connecting, the next fail in the _recvLoop function won't trigger reconnecting again:

gramjs/gramjs/network/MTProtoSender.ts

Lines 489 to 492 in 4a641ff

	if (!this.userDisconnected) {
	this._log.error(e);
	this._log.warn("Connection closed while receiving data");
	this.reconnect();

[Freihart512]

When will release this change?

[painor]

oh wow I forgot the port this over from https://github.com/Ajaxy/telegram-tt/blob/master/src/lib/gramjs/network/MTProtoSender.js#L172
Thanks for the find.