enable display of graph in html/pdf versions.

I'm applying the fixes made upstream in civicrm
(http://issues.civicrm.org/jira/browse/CRM-12926) to your patched
Graph.tpl. I'm not sure what your assessment is of moving to
googlegraph. Do you still think it's going in that direction?
Merge pull request #3 from jmcclelland/graph-image-in-print-version

enable display of graph in html/pdf versions.