add info about downloading pre-synced database (#293)
add info about downloading pre-synced database (#293)


shsmith/electrumx,erasmospunk/electrumx,thelazier/electrumx,Crowndev/electrumx,thelazier/electrumx,erasmospunk/electrumx,Crowndev/electrumx,shsmith/electrumx