Typo fix that drives to a XCode6 compilation error

```
/Pods/JVFloatLabeledTextField/JVFloatLabeledTextField/JVFloatLabeledTextField/JVFloatLabeledTextField.h:42:2: Prefix attribute must be followed by an interface or protocol
```

http://cl.ly/image/0k2q1W3Q471r
Merge pull request #1 from shouze/patch-1

Typo fix that drives to a XCode6 compilation error