Add contracts to ui-keyring (#137)

* add contracts to keyring

* genesisHash

* requested changes + allPlus option type

* remove duplicate fn

* add contracts to keyring

* genesisHash

* requested changes + allPlus option type

* remove duplicate fn

* changes

* contract key

* prefixes

packages/ui-keyring/src/observable/contracts.ts

@@ -0,0 +1,9 @@
+// Copyright 2017-2019 @polkadot/ui-keyring authors & contributors
+// This software may be modified and distributed under the terms
+// of the Apache-2.0 license. See the LICENSE file for details.
+
+import { contractKey } from '../defaults';
+
+import genericSubject from './genericSubject';
+
+export default genericSubject(contractKey);

packages/ui-keyring/src/observable/index.ts

@@ -7,13 +7,16 @@ import { map } from 'rxjs/operators';
 
 import accounts from './accounts';
 import addresses from './addresses';
+import contracts from './contracts';
 
 export default combineLatest(
   accounts.subject,
-  addresses.subject
+  addresses.subject,
+  contracts.subject
 ).pipe(
-  map(([accounts, addresses]) => ({
+  map(([accounts, addresses, contracts]) => ({
     accounts,
-    addresses
+    addresses,
+    contracts
   }))
 );