Added support for converting FloatObject to a float and NumberObject to an int; method is called as_numeric() in both classes.
For page merging, added additional argument to _mergePage so that it can access the CTM (transformation matrix); also added 'expand' argument to allow the new page to adopt the dimensons of the merged (and possibly transformed) page; defaults to false and is currently not used by any function, but will be once other methods are adapted to take the 'expand' parameter.