Major UI changes - including new icons!

- New UI icons for the tools, layer and frame buttons.
- Removed clone, remove and move frame buttons. You can now right click on a frame button to do these actions instead.
- Added first, previous, next and last frame buttons to the timeline.
- Added rulers for the main canvas viewport.
- Window size bumped to 1152x648.
- Default FPS is now 6 instead of 1.
- Fill tool renamed to Bucket.
- Mouse default cursor shape for the canvas is the arrow instead of cross.
- Mouse default cursor shape for the mirror and onion skinning buttons is the pointing hand.

project.godot

@@ -40,6 +40,34 @@ Global="*res://Scripts/Global.gd"
 gdscript/warnings/narrowing_conversion=false
 gdscript/warnings/return_value_discarded=false
 
+[display]
+
+window/size/width=1152
+window/size/height=648
+
+[importer_defaults]
+
+texture={
+"compress/bptc_ldr": 0,
+"compress/hdr_mode": 0,
+"compress/lossy_quality": 0.7,
+"compress/mode": 0,
+"compress/normal_map": 0,
+"detect_3d": true,
+"flags/anisotropic": false,
+"flags/filter": false,
+"flags/mipmaps": false,
+"flags/repeat": 0,
+"flags/srgb": 2,
+"process/HDR_as_SRGB": false,
+"process/fix_alpha_border": true,
+"process/invert_color": false,
+"process/premult_alpha": false,
+"size_limit": 0,
+"stream": false,
+"svg/scale": 1.0
+}
+
 [input]
 
 zoom_in={