v0.1 Alpha 2

Changes

• Updated skinned animation system
• Added Skinned Animation Poser
• Improved API for editor GUI
• Updated to SDL and removed GLFW for PC platforms
• Added gamepad support
• Trimmed type cache to reduce executable size
• Added Entity SetLayer method
• Added texture readback and render targets
• Added mesh thumbnails to the editor
• Updated ImGui and added transform manipulation using ImGuizmo
• Added unity-style Callback Components
• Minor API refactors