Docs: Updated README to include crates information

Included crates information into README.

Author: naveensrinivasan

README.md

@@ -33,6 +33,15 @@ production-worthy implementation in 2021.
 Communications for Rust-Lightning and Lightning Development Kit happens through
 [LDK slack](http://lightningdevkit.org/).
 
+Crates
+-----------
+1. [lightning](./lightning)
+1. [lightning-background-processor](./lightning-background-processor)
+1. [lightning-block-sync](./lightning-block-sync)
+1. [lightning-invoice](./lightning-invoice)
+1. [lightning-net-tokio](./lightning-net-tokio)
+1. [lightning-persister](./lightning-persister)
+
 About
 -----------
 LDK/Rust-Lightning is a generic library which allows you to build a lightning