chore(package): update scratch-paint to version 0.2.0-prerelease.20180808223211

Closes #2797

package.json

@@ -98,7 +98,7 @@
     "scratch-audio": "0.1.0-prerelease.20180625202813",
     "scratch-blocks": "0.1.0-prerelease.1533301486",
     "scratch-l10n": "3.0.20180803171042",
-    "scratch-paint": "0.2.0-prerelease.20180803171604",
+    "scratch-paint": "0.2.0-prerelease.20180808223211",
     "scratch-render": "0.1.0-prerelease.20180724152606",
     "scratch-storage": "0.5.1",
     "scratch-svg-renderer": "0.2.0-prerelease.20180712223402",