Huge demos update

-moved C stdlib function definitions to ecs_utils.utils
-added function to calculate mix(linear interpolation) and rsqrt(fast inverse sqrt)
-added some math to vec2 (length, normalize...)
-improved renderer with possibility to use multiple materials (one per block, not perfect solution for parallel compute, but works with some requirements)
-added blending support for material (opaque, additive, mixed)
-added Android support
-added gprahical representation for mouse tools (tool_circle.d)
-added initial support for editing template components variables
-better Component and Templates listing
-added possibility to add/removes components using mouse
-move CLocation to game_core.basic and reuse in every test
-moved tools code from demos to App (now code is fully separated from demos!)
-some improvement and fixes in Snake demo, with additional systems to handle adding and removing entities
-added new demo: Particles. By now demo has several particles to spawn and support for attractors and vortexes (calculation is made as every attractor with every entity)
-fixed bug with window hover and tools
-improved tool behaviour
-added new material
-now window is always opened as maximized windowed mode
-some minor fixes and improvements

demos/source/gui/attributes.d

@@ -0,0 +1,20 @@
+module gui.attributes;
+
+enum GUIColor = "GUIColor";
+
+struct GUIRange
+{
+    union 
+    {
+        struct
+        {
+            int min;
+            int max;
+        }
+        struct
+        {
+            float minf;
+            float maxf;
+        }
+    }
+}