convert existing xrpl library into a lerna monorepo

packages/xrpl/.nycrc

@@ -0,0 +1,10 @@
+{
+  "include": ["src/**/*.ts"],
+  "exclude": ["src/**/*.d.ts"],
+  "extension": [".ts"],
+  "require": ["ts-node/register"],
+  "reporter": ["text-summary", "html"],
+  "sourceMap": true,
+  "instrument": true,
+  "cache": true
+}