Mention vault opening

This way, it hopefully doesn't look like the program is hanging whenever
it is launched.

src/vault.rs

@@ -40,7 +40,7 @@ fn run(mut conn: Connection, mut rx: mpsc::UnboundedReceiver<Request>) {
     while let Some(request) = rx.blocking_recv() {
         match request {
             Request::Close(tx) => {
-                println!("Optimizing vault");
+                println!("Closing vault");
                 let _ = conn.execute_batch("PRAGMA optimize");
                 // Ensure `Vault::close` exits only after the sqlite connection
                 // has been closed properly.

src/vault/prepare.rs

@@ -1,6 +1,7 @@
 use rusqlite::Connection;
 
 pub fn prepare(conn: &mut Connection) -> rusqlite::Result<()> {
+    println!("Opening vault");
     conn.execute_batch(
         "
         CREATE TEMPORARY TABLE euph_trees (