Fix missing xaccTransCommitEdit() from r23466

Caused imported transactions to not be committed.

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@23562 57a11ea4-9604-0410-9ed3-97b8803252fd
BUG 336843 (Attach images/files/urls to transactions):

    - Added conditional to grey-out/disable 'Open File/Link' when association is unset
    - Converted 'Open Location' dialog to gtk_dialog_new_with_buttons
    - fixed invalid options from last submitted patch
    - made dialog modal



git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@23563 57a11ea4-9604-0410-9ed3-97b8803252fd