spreadsheet code cleanup

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@34607 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
fix for web spreadsheet keyListener not handling x,c,v chars correctly

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@34608 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
fix for web spreadsheet keyListener not recognizing mac command key 

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@34609 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e