ControlSize management and CPRuleEditor/CPPredicateEditor alignments

Hi guys,

Cocoa enables developers to use different control sizes : `Regular`, `Small` and `Mini`.

This PR enables Cappuccino developers to set their controls size via xCode or programmatically. Every control now has a `setControlSize:(CPControlSize)aSize` and a `controlSize` method which are the equivalent of [`NSCell` methods](http://goo.gl/nSZV6g)

## ControlSize management

Control size management has been done for the following **Aristo** and **Aristo2** controls :
* CPTextField
* CPButton
* CPPopUpButton
* CPCheckBox
* CPStepper
* CPDatePicker

*Note:* A new test named `CPControlSize` has been added to `Tests/Manuals` directory. Here are a screenshot for both theme:

**Aristo**
![cappuccino-aristo_controlsize](https://cloud.githubusercontent.com/assets/1447243/3885373/d0298d6a-21c0-11e4-948e-3474fd149471.png)

**Aristo2**

![cappuccino-aristo2_controlsize](https://cloud.githubusercontent.com/assets/1447243/3885375/d02ad15c-21c0-11e4-9e62-6ba15fc2b74b.png)

No new images is needed: `CPView` `setBackground` method uses CSS3 property `background-size` to set the correct background image size. 

## CPPredicateEditor/ CPRuleEditor alignments

As we now are able to set the control size, this PR also includes `CPRuleEditor` alignment corrections (issue [#2162](https://github.com/cappuccino/cappuccino/issues/2162) using `CPSmallControlSize` of each controls. The existing test in `Tests/Manual/CPPredicateEditorCibTest` has been updated to show the following right expressions : 
* Boolean
* CPDatePicker.
* CPPopUpButton

![cappuccino-cppredicateeditor](https://cloud.githubusercontent.com/assets/1447243/3885374/d029fa20-21c0-11e4-8f97-ed4377a65d5e.png)

Why no equivalent `CPDomDisplayServerSetStyleBackgroundSize`? The idea for these methods is to collect redundant changes. The dom optimisation functionality isn't actually enabled at the moment but if we do choose to enable it, it'd be nice if these were consistent. :)