Make AuthorityId generic (#1296)

* BlockAuthorityId convenience type

* Rename AuthorityId -> Ed25519AuthorityId to make it more precise

* Generalize AuthorityId up to substrate-client

* Fix in client-db

* rename: BlockAuthorityId -> AuthorityIdFor

* typo: should be digest item

* Fix test-runtime authorityId mismatch

One states that AuthorityId is u64 while the other states that it's Ed25519AuthorityId.

* Fix more u64 - Ed25519AuthorityId mismatch

* Fix compile of most of the srml modules

* Continue to pin aura and grandpa with ed25519 and fix compile

* Add MaybeHash trait

* Fix node-runtime compile

* Fix network tests

substrate/srml/aura/src/mock.rs

@@ -18,7 +18,7 @@
 
 #![cfg(test)]
 
-use primitives::{BuildStorage, testing::{Digest, DigestItem, Header}};
+use primitives::{BuildStorage, testing::{Digest, DigestItem, Header, UintAuthorityId}};
 use runtime_io;
 use substrate_primitives::{H256, Blake2Hasher};
 use {Trait, Module, consensus, system, timestamp};
@@ -34,7 +34,7 @@ pub struct Test;
 impl consensus::Trait for Test {
 	const NOTE_OFFLINE_POSITION: u32 = 1;
 	type Log = DigestItem;
-	type SessionKey = u64;
+	type SessionKey = UintAuthorityId;
 	type InherentOfflineReport = ();
 }
 
@@ -66,7 +66,7 @@ pub fn new_test_ext(authorities: Vec<u64>) -> runtime_io::TestExternalities<Blak
 	let mut t = system::GenesisConfig::<Test>::default().build_storage().unwrap().0;
 	t.extend(consensus::GenesisConfig::<Test>{
 		code: vec![],
-		authorities,
+		authorities: authorities.into_iter().map(|a| UintAuthorityId(a)).collect(),
 	}.build_storage().unwrap().0);
 	t.extend(timestamp::GenesisConfig::<Test>{
 		period: 1,