Fixed the navbar to the top.

Made the font of the inputs in vouchers bigger by 25%
Made the narration textarea minimum 5 lines
Changed the favicon to the old favicon

overlord/src/app/purchase/purchase.component.css

@@ -30,3 +30,7 @@
   left: 60px;
   top: 0;
 }
+
+mat-form-field.mat-form-field {
+  font-size: 1.25em;
+}