Core: Ensure classes match their header filename

Also drop some unused files.

Renamed:
- `core/dvector.h` -> `pool_vector.h`
- `core/io/resource_import.h` -> `resource_importer.h`
- `core/sort.h` -> `sort_array.h`
- `core/string_db.h` -> `string_name.h`

Dropped:
- `core/allocators.h`
- `core/os/shell.h`
- `core/variant_construct_string.cpp`

4 files changed, 2 insertions, 5 deletions

diff --git a/servers/visual/shader_language.h b/servers/visual/shader_language.h
index 185bad4222..acc3297bed 100644
--- a/servers/visual/shader_language.h
+++ b/servers/visual/shader_language.h
@@ -33,7 +33,7 @@
 
 #include "core/list.h"
 #include "core/map.h"
-#include "core/string_db.h"
+#include "core/string_name.h"
 #include "core/typedefs.h"
 #include "core/ustring.h"
 #include "core/variant.h"
diff --git a/servers/visual/visual_server_raster.cpp b/servers/visual/visual_server_raster.cpp
index 7be3bc562d..b18fabd467 100644
--- a/servers/visual/visual_server_raster.cpp
+++ b/servers/visual/visual_server_raster.cpp
@@ -33,7 +33,7 @@
 #include "core/io/marshalls.h"
 #include "core/os/os.h"
 #include "core/project_settings.h"
-#include "core/sort.h"
+#include "core/sort_array.h"
 #include "visual_server_canvas.h"
 #include "visual_server_global.h"
 #include "visual_server_scene.h"
diff --git a/servers/visual/visual_server_raster.h b/servers/visual/visual_server_raster.h
index e6434189f9..ec6e50753e 100644
--- a/servers/visual/visual_server_raster.h
+++ b/servers/visual/visual_server_raster.h
@@ -31,7 +31,6 @@
 #ifndef VISUAL_SERVER_RASTER_H
 #define VISUAL_SERVER_RASTER_H
 
-#include "core/allocators.h"
 #include "core/math/octree.h"
 #include "servers/visual/rasterizer.h"
 #include "servers/visual_server.h"
diff --git a/servers/visual/visual_server_scene.h b/servers/visual/visual_server_scene.h
index 539855bdc4..7583acd88f 100644
--- a/servers/visual/visual_server_scene.h
+++ b/servers/visual/visual_server_scene.h
@@ -33,7 +33,6 @@
 
 #include "servers/visual/rasterizer.h"
 
-#include "core/allocators.h"
 #include "core/math/geometry.h"
 #include "core/math/octree.h"
 #include "core/os/semaphore.h"
@@ -120,7 +119,6 @@ public:
 
 		VS::ScenarioDebugMode debug;
 		RID self;
-		// well wtf, balloon allocator is slower?
 
 		Octree<Instance, true> octree;