[lazarus] Updates

[Shane Miller]

Hi,

- TComboBox now throws ?ButtonDown messages and ?ButtonUp messages.

- Double click events now work (again).  
  There is a method in the Object Inspector (CurrentEditDblClick) that gets the double clicks from the object inspector so we could add events now.

- The "smart" hints for the object inspector disappear when you click on the object inspector or in the currentedit box.

Shane