code: def backUpDB() :
      
      st = time.ctime().replace(' ', '_')
      fn = conf.pyGeno_RABA_DBFILE.replace('.db', '_%s-bck.db' % st)
      shutil.copy2(conf.pyGeno_RABA_DBFILE, fn)
  
      return fn
docs: backup the current database version. automatically called by importGenome(). Returns the filename of the backup