Removed $recursive params: we always have to remove the children
gh-388
Override parent delete function, so we can run the onBeforeDelete check *BEFORE* starting to delete the children
gh-388
Shrink lft and rgt values after node deletion
gh-388
Delete all the subnodes, always reloading the info from the database.
Updated tests to check lft and rgt values of  other nodes, too.
gh-388
Added tests when onBeforeDelete returns false
If a subnode returns false, continue deleting the siblings, but don't delete the parent
gh-388
Added tests when the table is loaded
gh-388
Merge pull request #389 from akeeba/feature/388-fix-nested-delete

F0FTableNested - Fix delete