LP#1642344: XUL report cloning

LP#1642344: XUL report cloning

This patch allows report templates of version 4 and earlier
(which would have been created by the XUL staff client) to
be upgraded to template version 5 (used by the web staff
client) when the user clones a report. This closes a limitation
introduced in the reporter module for the web staff client.

Note that during the conversion, inner joins are used by
default when IDL classes have a 'has_a' relation rather than
defaulting to left outer joins, improving correctness of the
generated SQL query.

To test
-------
[0] Apply the patch.
[1] In a test database that has reporter templates created
    by (or for) the XUL staff client, create clones of
    those templates.
[2] Verify that the output of reports created using the new
    templates matches output of reports from the original
    templates.

Signed-off-by: Galen Charlton <gmc@equinoxinitiative.org>