Make sure to only pass strings to log

Closes connor4312#1.

src/Stats.ts

@@ -215,7 +215,7 @@ export class BlessedRenderer {
 
   public attach(stats: Stats, onExit: () => void) {
     this.stats = stats;
-    stats.on('log', (msg: string) => this.panels.log.log(msg));
+    stats.on('log', (msg: string) => this.panels.log.log(String(msg)));
     stats.on('draw', () => this.redraw());
     this.screen.key(['escape', 'q', 'C-c', 'enter'], onExit);
     this.screen.render();