#3915: frogs are back (problem with / in ImageManager)

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@30606 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
#3882 implementing continues in Web

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@30614 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e