[DONE][Suggestion] Instant events after mission success/failure/despawn

[Meridian]

You can now define events, that won't be "scheduled", but will pop up instantly for selected triggers:

1. `successEvents` = mission success
2. `failureEvents` = mission failure (does NOT include mission site despawn)
3. `despawnEvents` = mission site despawn

Each attribute is a weighted list.
One item is picked from the list randomly (considering weights).

Example:

Code: [Select]

alienDeployments:
  - type: STR_TERROR_MISSION
...
    successEvents:
      STR_TEST_EVENT1: 100
    despawnEvents:
      STR_TEST_EVENT2: 50
      STR_TEST_EVENT4: 50
    failureEvents:
      STR_TEST_EVENT3: 100
...