add two changes about "Argument Input Views"

Hello @ryanolsonk,

there are two changes i added for input behavior,

1. use picker to select fonts. 

![ios simulator screen shot 2014 7 27 7 20 31](https://cloud.githubusercontent.com/assets/670441/3713729/a45836ce-1580-11e4-99c5-3ec22962633f.png)

 2. add a "done" button for resign inputview.

![ios simulator screen shot 2014 7 27 7 20 58](https://cloud.githubusercontent.com/assets/670441/3713746/1f6b8cf8-1581-11e4-815a-b9c39a7c30ff.png)

thx.

Can we do 
```objc
UIToolbar *toolbar = [[UIToolbar alloc] init];
[toolbar sizeToFit];
```
to get the default toolbar size instead of hardcoding a height of 50 here?