If :name is passed to the supervisor, that name is used

[rockneurotiko]

Fixes #131

[versilov]

@rockneurotiko

Does not work for me. When I try to get file, referring bot by name, like this: ExGram.get_file(file_id, bot: bot), I get an error:

%ExGram.Error{
   code: nil,
   message: "No token available in the request, make sure you have the token setup on the config or you used the parameter \"token\" or \"bot\" correctly",
   metadata: nil
 }}}

[versilov]

So I am using version 0.40.0 now, it works well.