Bug 49528

When Inserting page number in e.g. a footer, one can choose a positive or negative offset (so that e.g. page 2 beccomes page 1). Such an offset can not be chosen when generating statistics, e.g. "total pages".

This is a problem if one wishes to create e.g. a frontpage for a book, that should not be counted as a page.

Steps to reproduce:
1. .... Insert -> Field -> page count 
2. .... Double click on the inserted page count.
3. .... On the screen one can choose between different formats, but not choose e.g. an offset.

If it is possible to insert an offset, then the UI is confusing, as the steps to inset an offset for page numbering is:

1 ... Insert -> Field -> page number
2 ... Double click on inserted page number
3 ... Choose offset