created svgedit main object, moved all namespaces handling in the same place

git-svn-id: http://svg-edit.googlecode.com/svn/trunk@2411 eee81c28-f429-11dd-99c0-75d572ba1ddd
set show_save_warning to camelCase

git-svn-id: http://svg-edit.googlecode.com/svn/trunk@2412 eee81c28-f429-11dd-99c0-75d572ba1ddd
fixed old Chrome bug handling for svg saving

git-svn-id: http://svg-edit.googlecode.com/svn/trunk@2413 eee81c28-f429-11dd-99c0-75d572ba1ddd