Update to Substrate master (#176)

* Update to master

This introduces a new type `CollatorId`, currently just `SessionKey`
but which would forseeably change to its own thing. It seems to work
like this (despite there being a lot of the new-incompatible
`AccountId` replaced). No idea if it does anything sensible, though.

* Cleanups

* Fix tests

* Remove commented code

* Specify commit hash

* Remove commented code

* Correct version

* Update runtime/Cargo.toml

Co-Authored-By: gavofyork <github@gavwood.com>

* PairT instead of _Pair

* Update lock file

* Remove rev causing upset

polkadot/validation/src/error.rs

@@ -16,9 +16,10 @@
 
 //! Errors that can occur during the validation process.
 
-use primitives::Ed25519AuthorityId as AuthorityId;
 use runtime_primitives::RuntimeString;
 
+use primitives::ed25519::Public as AuthorityId;
+
 error_chain! {
 	links {
 		Client(::client::error::Error, ::client::error::ErrorKind);