Fix OK/Clear/Cancel button order on below and above API 14 to match platform guidelines.

Android Lint currently gives this error:

>Layout uses the wrong button order for API >= 14: Create a layout-v14/filter.xml file with opposite order: OK button should be on the right (was "OK | Cancel | Clear", should be "Cancel | Clear | OK") (at line 41)

Also, the neutral button (Clear) should be in the middle.

I have changed the layout for API < 14 to OK | Clear | Cancel and API>= 14 to Cancel | Clear | OK as per the platform guidelines at http://developer.android.com/design/building-blocks/dialogs.html

Other discussion here: https://code.google.com/p/android/issues/detail?id=24138