Update mithril-client-wasm README

Author: Damien LACHAUME / PALO-IT

mithril-client-wasm/README.md

@@ -7,6 +7,7 @@
 * The different types of available data certified by Mithril are:
     * Snapshot: list and get.
     * Mithril stake distribution: list and get.
+    * Cardano transactions proofs: list & get commitment, get proofs
     * Certificate: list, get, and chain validation.
 
 ## Installation