Line_Locate_Point robustness(g, EndPoint(g)) != 1

[strk]

Robustness issues with ST_Line_Locate_Point make it hard to use it for noding:

=# with i as ( select '0102000000020000000000000000000000000000000000084000000000000034400000000000001040'::geometry as g ) select st_astext(g), st_line_locate_point(g, st_endpoint(g)) = 1 from i;
      st_astext       | ?column? 
----------------------+----------
 LINESTRING(0 3,20 4) | f
(1 row)

This is on a 32bit system with PostGIS trunk.

[strk]

Fixed and regress-tested by r8107