#4691 Polish root with NewtonSolver for Root[f, a, b]

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@37196 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
5.0.20.0

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@37197 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e