Feature/fix item levels (#41)

* Fix item levels

Fix name encoding in the admin (#40)

Feature/first item fix (#38)

* Fix first level item duplication

Feature/first item fix (#37)

* Fix first item removal issue

Adjust children structure to fix third level menu item (#35)

* Adjust children structure to fix third level menu item

Escape menu item name (#33)

* Escape menu item name

* Fix breadcrumbs

Fix third level menu items when they are added as custom items instea…

…d of categories (#31)

Remove unnecessary php 7 dependency

Merge pull request #29 from inviqa/feature/fix-default-styles

Feature/fix default styles

Merge pull request #28 from inviqa/feature/upgrade-module-version

Upgrade module version