feat: add tm2-js-client docs (#23)

* Add a Getting Started section

* Add base provider docs

* Add utility methods

* Add signer docs

* Add wallet docs

* Rename

* Add provider examples

* Add signer examples

* Add wallet docs

* Update docs to match latest API

Author: zivkovicmilos

tm2-js-client/api/provider/json-rpc-provider.md

@@ -0,0 +1,18 @@
+## JSON-RPC Provider
+
+Provider based on JSON-RPC HTTP requests.
+
+### new JSONRPCProvider
+
+Creates a new instance of the JSON-RPC Provider
+
+#### Parameters
+
+* `baseURL` **string** the JSON-RPC URL of the node
+
+#### Usage
+
+```ts
+new JSONRPCProvider('http://test3.gno.land:36657');
+// provider is created
+```