#4635 rewritten ToolTree and DraggableTool

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@37749 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Google drive restrictions for tablet

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@37750 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Google drive restrictions for tablet

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@37751 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
#4635 prevent self-dropping

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@37752 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Npe fix for #4770

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@37753 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e