Cache: implement LRU cache
Cache: create a  new non thread safe cache machanism
Merge branch 'master' of github.com:koding/cache into lru

# Please enter a commit message to explain why this merge is necessary,
# especially if it merges an updated upstream into a topic branch.
#
# Lines starting with '#' will be ignored, and an empty message aborts
# the commit.
Cache: add proper documentation
Cache: remove t/l operations from memory cache
Cache: add cache TTL struct
Cache: unify tests
Cache: create test for memory cache
Cache: return Cache interface instead of *LRUCache
Cache: rename MemoryCache to Memory
Cache: add package comments
Cache: add doc for exported error variable
Cache: add doc.go
Cache: rename LRUCache to LRU
Cache: rename MemoryCacheNoTS to MemoryNoTS
Cache: rename struct and add docs
Cache: remove unnecessary package comments
Cache: fix wording
Cache: implemented non thread safe LRU cache
Cache: fixed typo in doc.go