Enable jqplot for barchart, piechart and scatterchart

Patch by Andy Clayton

This doesn't work anymore due to changes in other parts of GnuCash, but
is a good starting point to fix it.

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@22787 57a11ea4-9604-0410-9ed3-97b8803252fd
Fix code to find html files

- look in pkg_data_dir as last resort (eg /usr/share/gnucash)
- effectively test all directories instead of only the second one
- add a debug print line

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@22788 57a11ea4-9604-0410-9ed3-97b8803252fd