Convert to gnc_file_dialog() to get the code to build on EL3/FC1.

[Derek Atkins]

Log Message:
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Convert to gnc_file_dialog() to get the code to build on EL3/FC1.

Tags:
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gnucash-gnome2-dev

Modified Files:
--------------
    gnucash/src/business/business-gnome:
        Makefile.am
        gnc-plugin-business.c
    gnucash/src/gnome:
        dialog-chart-export.c