restored type checking
Merge pull request #157 from timeck/restoreTypeChecks

restored type checking in Store.bulkComputeXXX() methods
remove CacheLoader interactions from Ehcache.putIfAbsent() and
Ehcache.replace(K, V)
Merge pull request #153 from timeck/putIfAbsentLoader

remove CacheLoader interactions from Ehcache.putIfAbsent() and Ehcache.replace(K, V)
Issue #41: Initial cut of cache event listener notification layer and relevant plumbing, though no actual events are wired in yet.
Issue #41: added event factory methods and store-initiated event support (expiration/eviction).