Changes

Add thunder changes event (#2317)

* Added ThunderChangesScriptEvent

Adds an event that allows a user to detect when thunder changes in a world

* Added newline to last end bracket

Simple update to adhere better to denizen formatting

* firstst attempt at corrections for thunderchangeevent pr

Remove `thunder` and `world` fields, replaced the if statements in `getContext` with a switch statement, and added the `in <world>` match that i originally forgot
 (commit: 74668a4)