Suggestion : Add ability to flush data based on LRU

[nitzanharel]

cache can grow endlessly and it would be a good idea to have an optional policy to flush/delete items from the cache based on an LRU.

[jaynel]

The whole point of the generational cache is to avoid managing metadata for individual items. The size of the cache is time dependent. If the cache is too big, use a shorter period between generations. If the rate of data growth is still too big for some reason, partition the data set and use more than one cache (the library currently doesn't support that because the ets tables have fixed names, but it would only require having a ets name table partitioning scheme).

I am not putting any new effort into maintaining this library as I am not spending time with erlang these days. Feel free to fork.