Scraper/Miner - Add string_cleaner

Signed-off-by: Dor Shaish <dor.shaish@intel.com>
Reddit_Miner: Abort retrieval flow if we are looping the same submissions

Signed-off-by: Dor Shaish <dor.shaish@intel.com>
Scraper + Miner: Work with search results

Signed-off-by: Dor Shaish <dor.shaish@intel.com>