chore(package): update scratch-paint to version 0.2.0-prerelease.20190715155430

Closes #4988

package.json

@@ -107,7 +107,7 @@
     "scratch-audio": "0.1.0-prerelease.20190114210212",
     "scratch-l10n": "3.3.20190711005050",
     "scratch-blocks": "0.1.0-prerelease.1561987297",
-    "scratch-paint": "0.2.0-prerelease.20190624133806",
+    "scratch-paint": "0.2.0-prerelease.20190715155430",
     "scratch-render": "0.1.0-prerelease.20190605151415",
     "scratch-storage": "1.3.2",
     "scratch-svg-renderer": "0.2.0-prerelease.20190523193400",