Bug 319598: Add support for saved tabular and graphical reports

(cherry-pick cc2fadc57316e44dff9ca1e22c040bf4fa665ee2 with modifications)

Conflicts:
	Bugzilla/User.pm
	template/en/default/global/messages.html.tmpl
	template/en/default/global/useful-links.html.tmpl
	template/en/default/global/user-error.html.tmpl
	template/en/default/reports/report.html.tmpl