Fully rework.
Introduce code style and mess tests.
Add support to enforce the trail status of an item.
Rework the matcher/voter system into real conditions.
Add support to "reduce" a tree and remove specific items.
Fix describe of the level condition.
Add new parent condition.
Make the sub-condition in the parent condition optional.
Add new item type condition.
Rename into bit3/php-flexi-tree.
Merge branch 'release/1.0'