Add an editor icon for the ImmediateMesh resource

editor/icons/ImmediateMesh.svg

@@ -0,0 +1 @@
+<svg height="16" viewBox="0 0 14.999999 14.999999" width="16" xmlns="http://www.w3.org/2000/svg"><path d="m2 2v2h5v-2zm5 2v3h2v-3zm2-2v2h5v-2zm-2 7v3h2v-3zm-5 3v2h5v-2zm7 0v2h5v-2z" fill="#ffca5f" transform="scale(.93749994)"/></svg>