refactor: Update examples to use .parse() instead of from_str

Switched example code in README and lib.rs documentation to use
Rust's standard FromStr::parse() method instead of explicit from_str
functions. This prepares for upcoming Bolt11Invoice FFI implementation
and makes the examples more idiomatic.

Author: alexanderwiederin

README.md

@@ -35,15 +35,15 @@ fn main() {
 
 	// .. fund address ..
 
-	let node_id = PublicKey::from_str("NODE_ID").unwrap();
-	let node_addr = SocketAddress::from_str("IP_ADDR:PORT").unwrap();
+	let node_id = "NODE_ID".parse().unwrap();
+	let node_addr = "IP_ADDR:PORT".parse().unwrap();
 	node.open_channel(node_id, node_addr, 10000, None, None).unwrap();
 
 	let event = node.wait_next_event();
 	println!("EVENT: {:?}", event);
 	node.event_handled();
 
-	let invoice = Bolt11Invoice::from_str("INVOICE_STR").unwrap();
+    let invoice = "INVOICE_STR".parse().unwrap();
 	node.bolt11_payment().send(&invoice, None).unwrap();
 
 	node.stop().unwrap();

src/lib.rs

@@ -24,7 +24,6 @@
 //!
 //! ```no_run
 //! use ldk_node::Builder;
-//! use ldk_node::lightning_invoice::Bolt11Invoice;
 //! use ldk_node::lightning::ln::msgs::SocketAddress;
 //! use ldk_node::bitcoin::Network;
 //! use ldk_node::bitcoin::secp256k1::PublicKey;
@@ -44,15 +43,15 @@
 //!
 //! 	// .. fund address ..
 //!
-//! 	let node_id = PublicKey::from_str("NODE_ID").unwrap();
-//! 	let node_addr = SocketAddress::from_str("IP_ADDR:PORT").unwrap();
+//! 	let node_id = "NODE_ID".parse().unwrap();
+//! 	let node_addr = "IP_ADDR:PORT".parse().unwrap();
 //! 	node.open_channel(node_id, node_addr, 10000, None, None).unwrap();
 //!
 //! 	let event = node.wait_next_event();
 //! 	println!("EVENT: {:?}", event);
 //! 	node.event_handled();
 //!
-//! 	let invoice = Bolt11Invoice::from_str("INVOICE_STR").unwrap();
+//! 	let invoice = "INVOICE_STR".parse().unwrap();
 //! 	node.bolt11_payment().send(&invoice, None).unwrap();
 //!
 //! 	node.stop().unwrap();