Add support for non-core subprojects, and a separate coverage thershold
value for them. I still need to update CDash's coverage views to use
these new capabilities, but this commit lays the ground work.

SVN revision: 3507
BUG: 14939 Make user statistics calculation PostgreSQL-compatible (by Igor)

SVN revision: 3509
ENH: 14940: Add build name and site name to summary email

SVN revision: 3510
BUG: fix failing tests due to typo in cdash.sql

SVN revision: 3511
BUG: Added baselineimage as a name for the interactive image viewer

SVN revision: 3513
COMP: Missing test to tell the administrator to upgrade

SVN revision: 3514
ENH: 14942 Improve index page layout a bit (by Igor)

SVN revision: 3515