def register(name, klass)
      raise ProxyFetcher::Exceptions::RegisteredProvider, name if providers.key?(name.to_sym)

      providers[name.to_sym] = klass
    end
def register(name, klass)
      raise ProxyFetcher::Exceptions::RegisteredProvider, name if providers.key?(name.to_sym)

      providers[name.to_sym] = klass
    end
Add custom provider to common registry.
 Requires proxy provider name ('xroxy' for example) and a class
 that implements the parsing logic.

 @param name [String, Symbol]
   provider name

 @param klass [Class]
   provider class

 @raise [ProxyFetcher::Exceptions::RegisteredProvider]
   provider already registered