Fix for always-false ineqs being drawn as always-true (#2551 related)

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@31108 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
* Adding support for newer grobcov libraries (SingularWS)
* Using grobcov library for LocusEquation if possible

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@31109 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e