anchor.diff:        LResource.SpecificURL := AURL;
         LResource.SpecificToken := AToken;
         LResource.SpecificAccept := AAccept;
  +      FireBeforeExecute(LResource.URL, LClient);
         Result := LResource.GETAsString();
       finally
         LResource.Free;
  
positive.code:     ApplyProxyConfig;
  end;
  
  constructor TMARSCustomClient.Create(AOwner: TComponent);
  begin
    inherited;
  
negative.code:   // to be implemented in inherited classes
  end;
  
  class procedure TMARSCustomClient.FireBeforeExecute(const AURL: string;
    const AClient: TMARSCustomClient);
  var
    LProc: TMARSClientBeforeExecuteProc;
  begin
    for LProc in FBeforeExecuteProcs do
      LProc(AURL, AClient);
  end;
  
  procedure TMARSCustomClient.Get(const AURL: string; AResponseContent: TStream;
    const AAuthToken: string; const AAccept: string; const AContentType: string);
  begin
  