anandsiddharth/laravel-paytm-wallet paytm gateway integration

There is no seperate config file for paytm. All the configurations are stored
inside the `config/services.php` file, so you don't have to edit your env file.
you can link it to seperate config file by creating `config/paytm.php` and just
update paytm configurations inside the services.php file

'paytm-wallet' => [
  'env' => config('paytm.env'), // values : (local | production)
  'merchant_id' => config('paytm.m_id'),
  'merchant_key' => config('paytm.m_key'),
  'merchant_website' => config('paytm.website'),
  'channel' => config('paytm.channel_id'),
  'industry_type' => config('paytm.industry_type_id'),
],

And then inside `config/paytm.php` add that configurations.