formatter can have backward-slash too
formatter can have backward-slash too

* backward slashes `\` are used in namespaces
* in theory forward slashes `/` shouldn't be used, but we should leave them here for compatibility reasons
xepan/atk4,xepan/atk4,atk4/atk4,xepan/atk4,atk4/atk4,atk4/atk4,atk4/atk4