App versions

Please review @ssorallen 
These can be "subclasses" of `.caret`:

```
.caret-right {
  border-color: transparent #f6f6f6;
  border-width: 5px 5px 5px 0;
}

.caret-left {
  border-color: transparent #f6f6f6;
  border-width: 5px 0 5px 5px;
}
```

```
  <span class="caret caret-right"></span>
```