Merge pull request #237 from onflow/reward-slashing

Adds rewards slashing transaction

templates/capability_set_slashing_nodes.cdc

@@ -0,0 +1,24 @@
+import FlowIDTableStaking from 0x8624b52f9ddcd04a
+
+/// This transaction uses a staking admin capability
+/// to set a list of nodes whose rewards will be decreased
+/// during the next rewards payout
+
+transaction(nodesToSlash: {String: UFix64}) {
+
+    // Local variable for a reference to the ID Table Admin object
+    let adminRef: &FlowIDTableStaking.Admin
+
+    prepare(acct: AuthAccount) {
+        let adminCapability = acct.copy<Capability>(from: FlowIDTableStaking.StakingAdminStoragePath)
+            ?? panic("Could not get capability from account storage")
+
+        // borrow a reference to the admin object
+        self.adminRef = adminCapability.borrow<&FlowIDTableStaking.Admin>()
+            ?? panic("Could not borrow reference to staking admin")
+    }
+
+    execute {
+        self.adminRef.setNonOperationalNodesList(nodesToSlash)
+    }
+}