Ensure that cell is pointed to the right cell when retrieving the price

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@23758 57a11ea4-9604-0410-9ed3-97b8803252fd
Bug 721770 - "Choose accounts to create" has no effect

"Common Accounts" always created

Conditionally adjust the page number selection in the on_prepare
function to account for the extra page.

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@23759 57a11ea4-9604-0410-9ed3-97b8803252fd