New Features and Bug Fixes

• Complete rebuild of the Canvas library architecture.
• Implemented Pixel Grid.
• Customize color of Pixel Grid.
• Implemented smart Snapping Guides.
• Customize color and magnetic threshold of Snapping Guides.
• Allow items resizing in all directions.
• Add images via click and drag with the Image Tool.
• Handle multiple Fills and Border colors for each item.
• Allow scaling items from the center.
• Enable dropping images on the canvas.
• A lot of code improvements and optimization.