Made unit tests easier to add. New suites now just need to be added to two lines...

Made unit tests easier to add.  New suites now just need to be added to two lines in cu_tester.c, no changes to header files necessary, new tests need one line in the appropriate .c file.  From Jeff Adams.

git-svn-id: http://svn.osgeo.org/postgis/trunk@5329 b70326c6-7e19-0410-871a-916f4a2858ee