-improved WASM compilation scripts

-added external bindbc.sdl import for WASM
-working on demos (WIP, working simple demo with ECS and SDL2)
-small change in ecs.std

demos/external/imports/bindbc/sdl/bind/sdlshape.d

@@ -0,0 +1,63 @@
+
+//          Copyright Michael D. Parker 2018.
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+module bindbc.sdl.bind.sdlshape;
+
+import bindbc.sdl.config;
+import bindbc.sdl.bind.sdlpixels : SDL_Color;
+import bindbc.sdl.bind.sdlstdinc : SDL_bool;
+import bindbc.sdl.bind.sdlsurface : SDL_Surface;
+import bindbc.sdl.bind.sdlvideo : SDL_Window;
+
+enum {
+    SDL_NONSHAPEABLE_WINDOW = -1,
+    SDL_INVALID_SHAPE_ARGUMENT = -2,
+    SDL_WINDOW_LACKS_SHAPE = -3,
+}
+
+enum WindowShapeMode {
+    ShapeModeDefault,
+    ShapeModeBinarizeAlpha,
+    ShapeModeReverseBinarizeAlpha,
+    ShapeModeColorKey
+}
+mixin(expandEnum!WindowShapeMode);
+
+enum SDL_SHAPEMODEALPHA(WindowShapeMode mode) = (mode == ShapeModeDefault || mode == ShapeModeBinarizeAlpha || mode == ShapeModeReverseBinarizeAlpha);
+
+union SDL_WindowShapeParams {
+    ubyte binarizationCutoff;
+    SDL_Color colorKey;
+}
+
+struct SDL_WindowShapeMode {
+    WindowShapeMode mode;
+    SDL_WindowShapeParams parameters;
+}
+
+version(BindSDL_Static) {
+    extern(C) @nogc nothrow {
+        SDL_Window* SDL_CreateShapedWindow(const(char)*,uint,uint,uint,uint,uint);
+        SDL_bool SDL_IsShapedWindow(const(SDL_Window)*);
+        int SDL_SetWindowShape(SDL_Window*,SDL_Surface*,SDL_WindowShapeMode*);
+        int SDL_GetShapedWindowMode(SDL_Window*,SDL_WindowShapeMode*);
+    }
+}
+else {
+    extern(C) @nogc nothrow {
+        alias pSDL_CreateShapedWindow = SDL_Window* function(const(char)*,uint,uint,uint,uint,uint);
+        alias pSDL_IsShapedWindow = SDL_bool function(const(SDL_Window)*);
+        alias pSDL_SetWindowShape = int function(SDL_Window*,SDL_Surface*,SDL_WindowShapeMode*);
+        alias pSDL_GetShapedWindowMode = int function(SDL_Window*,SDL_WindowShapeMode*);
+    }
+
+    __gshared {
+        pSDL_CreateShapedWindow SDL_CreateShapedWindow;
+        pSDL_IsShapedWindow SDL_IsShapedWindow;
+        pSDL_SetWindowShape SDL_SetWindowShape;
+        pSDL_GetShapedWindowMode SDL_GetShapedWindowMode;
+    }
+}