Fix .gitignore: stop tracking ignored files

backend/lib/openzeppelin-contracts/scripts/generate/templates/Checkpoints.opts.js

@@ -0,0 +1,22 @@
+// OPTIONS
+const VALUE_SIZES = [224, 160];
+
+const defaultOpts = size => ({
+  historyTypeName: `Trace${size}`,
+  checkpointTypeName: `Checkpoint${size}`,
+  checkpointFieldName: '_checkpoints',
+  keyTypeName: `uint${256 - size}`,
+  keyFieldName: '_key',
+  valueTypeName: `uint${size}`,
+  valueFieldName: '_value',
+});
+
+module.exports = {
+  OPTS: VALUE_SIZES.map(size => defaultOpts(size)),
+  LEGACY_OPTS: {
+    ...defaultOpts(224),
+    historyTypeName: 'History',
+    checkpointTypeName: 'Checkpoint',
+    keyFieldName: '_blockNumber',
+  },
+};