Merge remote-tracking branch 'origin/master' into...

Merge remote-tracking branch 'origin/master' into dp/make-CallExecutors-generic-over-hasher-and-rlpcodec

* origin/master:
  Fixed sync stalling when import queue is full (#691)
  New extrinsic dispatch model (#678)
  remove parachain's Cargo.lock (#682)
  Implement json metadata for outer events (#672)
  Improvements to the Kademlia system (#688)
  Use BufReader and BufWriter (#684)
  Switch to using parity/rust:substrate which has rust nightly-2018-08-31 (#686)
  Update to latest libp2p (#673)
  Implement storage json metadata (#670)
  impl MaybeEmpty for H256 and u64 (aka AccountId in prod/tests) (#665)
  Speedup compilation (#671)
  Remove requirement of function indices for decl_module! (#666)
  DigestItem trait (v2) (#650)