reverse convex orientation >> reverse orientation for 2D polygons (+z or -z)

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@30802 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Fix update sides with regular bottom

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@30806 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Fix updates with regular bottom

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@30807 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e