[giac] use threads again (JNI)

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@25989 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
[giac] fix RandomPolynomial (last fix was wrong)

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@25990 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
[giac] turn threads off again (JNI)

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@25991 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
GeoCurveCartesian3D implements Path

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@25992 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e