Log checked headers for deal events

- mark header as checked if no matching logs
- mark header as checked if all matching logs persisted successfully
- batch convert and insert matching logs to enable transactional persist
- enable skipping previously checked block headers when restarting a sync

db/migrations/1537389741_add_deal_to_checked_headers.down.sql

@@ -0,0 +1,2 @@
+ALTER TABLE public.checked_headers
+    DROP COLUMN deal_checked;

db/migrations/1537389741_add_deal_to_checked_headers.up.sql

@@ -0,0 +1,2 @@
+ALTER TABLE public.checked_headers
+    ADD COLUMN deal_checked BOOLEAN NOT NULL DEFAULT FALSE;

db/schema.sql

@@ -669,7 +669,8 @@ ALTER SEQUENCE public.blocks_id_seq OWNED BY public.blocks.id;
 CREATE TABLE public.checked_headers (
     id integer NOT NULL,
     header_id integer NOT NULL,
-    price_feeds_checked boolean DEFAULT false NOT NULL
+    price_feeds_checked boolean DEFAULT false NOT NULL,
+    deal_checked boolean DEFAULT false NOT NULL
 );