changelog file had extra linebreak

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code rework progress
more code changes, files moved around, new feats

* CODE: Began splitting code into multiple namespaces to organize it
better.
Splitting to multiple projects is not preferred because that requires
supplying dlls or meddling with assembly merging software.
* CODE: Began changing clunky cross-class updates into proper way of
doing them (events)
* Fixed a small bug with autosave timer (actual autosave timer was not
updated upon loading settings from file)
* Significant performance improvement when navigating large missions
(like TSN Sandbox):
Changing current event in large missions took noticable time before,
should be instantanious now
(or at least as fast as if the mission contains only several events)
* Significant reduction in the amount of memory used for holding
undo/redo states (basically, we compress them in memory now)
* New setting: you can now choose how many undo options are preserved
upon saving a mission, so that you can undo even after you have just
saved.
* New setting: fix flickering in tree view controls when redrawing,
enabled by default.
This fix can introduce artifacts when scrolling tree view while dragging
a node, so you may want to disable it.