#36 A problem when adding new pages to a notebook.

[Wei-Cheng Cheng]

When trying to add a new page to an existing notebook,
the page structure would be changed. If there are
fragments that are delineated from that notebook, then
an 'out-of-syn' waring message would be displayed.

The system needs to be able to handle this. We only
consider the case when adding new pages to an
existing notebook. (No deletion or replacement)

The solution would be to change the 'pagenumber'
attribute in the Excerpt table to 'page' as the type of
string. Instead of keeping track of the page number, we
use the page file name.