Middlewares refactored to multiple files in middleware package.

Extractors removed as they introduce complexity to scraper. Both in learning and developing.

export/export.go

@@ -1,7 +1,6 @@
 package export
 
 // Exporter interface is for extracting data to external resources.
-// Geziyor calls every extractors Export functions before any scraping starts.
 // Export functions should wait for new data from exports chan.
 type Exporter interface {
 	Export(exports chan interface{})