#2506 regress failure on 32-bit windows PostgreSQL.  Round values so match on all platforms

git-svn-id: http://svn.osgeo.org/postgis/branches/2.1@12029 b70326c6-7e19-0410-871a-916f4a2858ee
#2506 regress failure on 32-bit windows PostgreSQL.  More stringent round but also subtract to guarantee they are the same

git-svn-id: http://svn.osgeo.org/postgis/branches/2.1@12031 b70326c6-7e19-0410-871a-916f4a2858ee