* Removed the Interfaces folder.
* All objects inside the GameObjects subfolders are now in the GameObjects namespace.
* Added a Resharper DotSettings file to mark the GameObjects subfolders as not providing namespaces.
* Simplified Robust.client.Graphics namespace.
* Automated remove redundant using statements.
Made it so keybinds don't block other keybinds from firing.
Why is this necessary? This allows us to have "same keybind, different functionality" binds sanely, like shift click being both TextCursorSelect and (in content) ExamineEntity. Before this change the latter was temporarily broken in UI controls because of TextCursorSelect taking priority and instantly treating the event as handled because it's CanFocus.
The offshoot of this is that all the "args.CanFocus == mouse left" UI code had to be fixed, since multiple things were now firing for that and breaking everything. For example TextCursorSelect actually BROKE because now ExamineEntity was firing inside UI again and that was seen as a left click.
EngineKeyFunctions.UIClick has been introduced as "mouse left for the UI" for this purpose.
* Refactor Controls to default to MouseFilterMode.Ignore
* Clean up MouseFilterMode.Ignore from Controls
* Fix BoxContainer eating UI clicks
* Fix ScrollContainer using the wrong variable
* Refactor ContainerButtons to use a StyleClass for formatting instead of typeof
* Refactor BaseButton to work when child has MouseFilter.Pass
