- added process_dbdesc function
- added dbdesc block to process_packet function
- changed lsdb lsa list array to nlist instead of list type to reduce
lsa search times
- changed add_to_nlist to pass in object and key and malloc new nlist
item inside function instead of recieving a new replay_nlist item (this
mirrors an earlier change in add_to_list for replay_list structs)
- added have_lsa function which returns 1 if lsa is found in lsdb (else
returns 0)