Update & save unlockables when visiting a new map

Resolves #1122 (closed)

This test file has a test unlockable, which is unlocked by visiting GFZ1. In 2.2.13, it only unlocks when doing something else that refreshes unlockables; this includes closing and reopening the game, grabbing an emblem, beating a level, activating an unlockable trigger, or beating the campaign. In this branch, it unlocks immediately when the condition is met.

emblem-fix-test.pk3