Moved common options panel from C# and VB.NET to base.
Fixed bug in property pad by introducing PropertyContainer (combined set of DesignerHost, SelectableObjects and SelectedObject).
The PropertyPad now automatically shows the PropertyContainer of the active ViewContent.
git-svn-id: svn://svn.sharpdevelop.net/sharpdevelop/trunk@109 1ccf3a8d-04fe-1044-b7c0-cef0b8235c61