Inserting few documents(with dummy values) into the collection

(A) Inserted file: filldb.py 
     This file contains code that:
     - Inserts documents into GSystemType and GSystem collection
     - Creates '.json' file for each newly created document under it's corresponding rcs-repo collection
     - Handles histrory creation also, i.e. initial checkin command.

(B) Updated INSTALLATION file