#2713 flag ST_ForceCurve as a curve function

git-svn-id: http://svn.osgeo.org/postgis/trunk@12484 b70326c6-7e19-0410-871a-916f4a2858ee
#2713: properly cast text to geom (don't enforce bad habits), flag ST_StartPoint and ST_EndPoint as working with CIRCULARLINSTRINGS

git-svn-id: http://svn.osgeo.org/postgis/trunk@12485 b70326c6-7e19-0410-871a-916f4a2858ee