Join event is not handled if the username is not lowercase

[zusorio]

If the username is not lowercase the Join event is not detected which breaks joining channels after the bot is initialized and stops the emission of join events. There should be either an error when the username is not lowercase, automatically changing the username to lowercase or just detect the username when it is lowercase.

[kamerat]

+1!
I pulled my hair not understanding why the bot did not connect..
Can confirm I had capitalized name "Myname" and .join event never fired.