[TASK] Respect argument showHiddenInMenu

Fixes #691.
Are you sure you want that behavior? I personally would expect that just those items that have nav_hide would disappear. Fx rawRootline:  level0 -> level1 -> level2 ... if now level1 has nav_hide true, i would expect the output to be level0 -> level2, but as far as i read your PR it will just output level0