Fix status button on dashboard

![fix-status-button](https://cloud.githubusercontent.com/assets/1078430/3279431/7d02126c-f3fb-11e3-9603-2e0422bbbea5.gif)

http://forums.hummingbird.me/t/feed-post-button-problem/10346

At first I tried to modify `.status-form` by shortening its height and adding a bottom margin, but seems like `append: '\n'` setting of the autosize plugin is there for a good reason. So I went for this instead.