Patch from Igor:

Currently Rhino source has quite a few places with code like (String)node.getDatum()
 or ((Number)node.getDatum()).doubleValue(). The patch changes this usage to call
node.getString() or node.getDouble().

It also adds new constructors to Node to accept int or double values in addition to
Object datum to replace new Node(token, new Integer(x)) by Node(token, x) etc. It
may allow in future not to create a wrapper object for int or double datum to speed
up parsing.