First version for combined EventHandler (web and touch)

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@37917 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Ticket #4660: it seems this was the intended behaviour about getCursor3D... but sticky points as such are still not handled

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@37918 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
documentation for new classes

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@37919 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e