Add an asset editor

[PunkPun]

Currently it's very difficult to get precise offsets artwork, or turrets / barrels. The current workflow is changing the yamls, and then reloading the entire game. When you need to do it only a few times it's fine, but often you have to do it tens or hundreds of times.

This solution lets you see how the changes affect the assets and also has an export option for easy copy paste.

The way it's implemented: It does memberwise copies of trait infos and sprites on opening the asset editor, this way it doesn't affect anything ingame. I use quite a bit of reflection, I wonder how much of it should be done in a non-magic manner. This is also an early implementation, its functionality will grow a lot over time

When editing sequence offsets it doesn't handle combined sequences properly