gwt: use canvas defined in html

- handle resize in js
- app option for tileSize in MapConfig js object

vtm-web-app/build.gradle

@@ -79,9 +79,16 @@ task copyVtmAssets(type: Copy) {
     include '**/*'
 }
 
+task copyWarSources(type: Copy) {
+    from 'war/index.html'
+    from 'war/default.css'
+    into "src/main/webapp"
+}
+
 tasks.withType(JavaCompile) { compileTask ->
   compileTask.dependsOn copyThemeAssets
   compileTask.dependsOn copyVtmAssets
+  compileTask.dependsOn copyWarSources
 }
 
 // Configuring Eclipse classpath