synchronize panel writing with UI thread
synchronize panel writing with UI thread

If we don't synchronize, the 'append' command won't work when
called from .set_timeout_async(). Potential ST bug.

guillermooo/dart-sublime-bundle,guillermooo/dart-sublime-bundle,guillermooo-forks/dart-sublime-bundle,guillermooo-forks/dart-sublime-bundle,guillermooo/dart-sublime-bundle,guillermooo/dart-sublime-bundle,guillermooo-forks/dart-sublime-bundle,guillermooo-forks/dart-sublime-bundle