[ts] Added canvas backend stub

spine-ts/build.sh

@@ -3,4 +3,5 @@ set -e -x
 tsc -p tsconfig.json
 tsc -p tsconfig.core.json
 tsc -p tsconfig.webgl.json
+tsc -p tsconfig.canvas.json
 tsc -p tsconfig.widget.json

spine-ts/tsconfig.canvas.json

@@ -0,0 +1,23 @@
+{
+	"compilerOptions": {
+		"module": "none",
+		"noImplicitAny": true,
+		"removeComments": false,
+		"preserveConstEnums": true,
+		"outFile": "build/spine-canvas.js",
+		"sourceMap": true,
+		"declaration": true
+	},
+	"include": [
+		"core/src/**/*",
+		"canvas/src/**/*"
+	],
+	"exclude": [
+		"webgl/src/*.ts",
+		"widget/src/*.ts",
+		"build",
+		"build/*.d.ts",
+		"build/*.js",
+		"build/*.js.map"	 
+	]
+}