- test memcached

- test refresh

- add cost-based caching strategy

- add shared memory store

- cleanup logging

- remove all die/confess statements except where they are in the init phase

- remove debugging to STDERR

- add better way of getting cache stats

- add way of getting cache sizes out

- honour function strategy directives in config

- honour function stratgey parameter in code

- refactor strategy API to completely seperate record creation from
  retreival/setting