convert old saved files (localStorage) to local files of device

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@38288 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Code cleaning

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@38289 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e