developing
	modified:   forest-core/src/main/java/fengfei/forest/slice/Navigator.java
	modified:   forest-core/src/main/java/fengfei/forest/slice/Slice.java
	modified:   forest-core/src/main/java/fengfei/forest/slice/impl/AccuracyRouter.java
	modified:   forest-core/src/main/java/fengfei/forest/slice/impl/NavigableRouter.java