Integrated various changes worked on at the Glasgow Science Center. Changes

include change the CameraManipulators so they work with double for time
instead of float.  Also added support for DataType to osg::StateAttribute
and StateSet so that they can be set to either STATIC or DYNAMIC, this
allows the optimizer to know whether that an attribute can be optimized
or not.

src/osg/StateSet.cpp

@@ -17,6 +17,7 @@ using namespace osg;
 StateSet::StateSet()
 {
     _renderingHint = DEFAULT_BIN;
+    _datatype = osg::StateAttribute::STATIC;
     
     setRendingBinToInherit();
 }
@@ -40,6 +41,7 @@ StateSet::StateSet(const StateSet& rhs,const CopyOp& copyop):Object(rhs,copyop)
     _binMode = rhs._binMode;
     _binNum = rhs._binNum;
     _binName = rhs._binName;
+    _datatype = rhs._datatype;
 }
 
 StateSet::~StateSet()