ISWordDocument; added new Append2 function

A new function, Append2, has been added to ISWordDocument.

This is similar to Append, but does things slightly differently to better handle default/ normal styles in Word documents. Therefore the existing Append function is still available and can continue to be used in most cases.

Every document has its own set of default formatting/ style properties. This means if you add one document into another, all default properties from the second document will start using the first document's default properties - as there can only be one default.

One way around this is to override default styles in the document, i.e. so it doesn't use default styles. Alternatively, try using the new Append2 function.