Add Not Most Recently Used Cache replacement policy

[brsf11]

Just another cache policy commonly used. Choose randomly from blocks that are not most recently used.

[jdupak]

@ppisa Looks fine by me

[jdupak]

@ppisa Can we merge this?

[ppisa]

@ppisa Can we merge this?

The implementation is clear, straightforward, fits and fills place for extension. It can be merged. I am not sure (doubt) how uses-full it is for practical use, but it can be good aid for some education/comparison/analysis.