message: add description for storage
diff: name = "storage"
  version = "0.1.0"
  authors = ["Vincent Hanquez <vincent.hanquez@iohk.io>", "Nicolas Di Prima <nicolas.diprima@iohk.io>"]
  +keywords = [ "Cardano", "Storage", "Immutable", "FileSystem" ]
  +description = """
  +The cardano storage library. It provides 2 different levels of functionality, from lowlevel
  +fast immutable or append only file without any assumption about the data, to a higher level
  +intertwined with the cardano blockchain
  +"""
  [dependencies]
  cryptoxide = { path = "../cryptoxide" }
  