[FEATURES] Add cache runtime for cachefs

[eryugey]

What feature you'd like to add:

Add cachefs as a new CacheFSRuntime to cache & accelerate thinruntime dataset. Cachefs is a distributed filesystem that cache & accelerate any given POSIX directory with distributed cache.

Why is this feature needed:

ThinRuntime was implemented to make general storage like oss/nas easier to integrate with fluid, but thinruntime doesn't have the ability to cache data access on thinruntime. So we need a new cache runtime that could cache any POSIX dir, so there's a general way to cache any thinruntime backend.