Fixed bug Sitecrawler Distributed crawler

*Almost cleaned bug
Revert "Fixed bug Sitecrawler Distributed crawler"

This reverts commit 47181158b5e18fedcb18e014c9f81f68c5035e53.
Revert "Revert "Fixed bug Sitecrawler Distributed crawler""

This reverts commit cafd23afb0e9c56ad8786f1ef3a8517a1ed0cea0.
Excluded database file

*Excluded crawler.sqlite3 & webpage.sqlite3