v0.0.0a6

• Updated documentation
• Added .signed(...) constructor to dapp.EventInput
• Added .verify(...) method to dapp.ED25519
• Renamed http.DappService to http.DAppService
• Renamed classmethods ._(...) to .di(...) in http.HTTPService, http.DAppService & http.DeliveryService
• Re-exported service classes (http.HashService, http.EventService, http.DAppService, http.ChannelService, http.PostService, http.MessageService, http.DeliveryService) from http.dapp and http.delivery through the main http package namespace