Remove the std feature implications from the lightning crate

Now that we don't have to have everything in our entire ecosystem
use the same `std`/`no-std` feature combinations we should start by
untangling our own features a bit.

This takes one last step, removing the implications of the `std`
feature from the `lightning` crate.

Author: TheBlueMatt

lightning/Cargo.toml

@@ -30,7 +30,7 @@ max_level_trace = []
 unsafe_revoked_tx_signing = []
 
 no-std = ["hashbrown", "possiblyrandom", "libm"]
-std = ["lightning-invoice/std", "bech32/std"]
+std = []
 
 # Generates low-r bitcoin signatures, which saves 1 byte in 50% of the cases
 grind_signatures = []

lightning/src/ln/bolt11_payment.rs

@@ -188,11 +188,12 @@ mod tests {
 
 		let secp_ctx = Secp256k1::new();
 		let node_secret = nodes[1].keys_manager.backing.get_node_secret_key();
+		let time = std::time::SystemTime::now().duration_since(SystemTime::UNIX_EPOCH).unwrap();
 		let invoice = InvoiceBuilder::new(Currency::Bitcoin)
 			.description("test".into())
 			.payment_hash(Sha256::from_slice(&payment_hash.0).unwrap())
 			.payment_secret(payment_secret)
-			.current_timestamp()
+			.duration_since_epoch(time)
 			.min_final_cltv_expiry_delta(144)
 			.amount_milli_satoshis(50_000)
 			.payment_metadata(payment_metadata.clone())