#3401 command ClosestPoint gives the closest point from point to function.

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@28630 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
#3401 removed third parameter

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@28631 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
typo

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@28632 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e