Added links/references to README
Added links/references to README

Added a number of links and references to manuscripts associated with
databases used here

uomsystemsbiology/LMMEL-miR-miner,uomsystemsbiology/LMMEL-miR-miner,uomsystemsbiology/LMMEL-miR-miner,uomsystemsbiology/LMMEL-miR-miner,uomsystemsbiology/LMMEL-miR-miner