updating to include initialization in func
Update store to use sets.Set
updating tests to use sets.New instead of sets.NewString
update store_test
update index_test
update controller_test file
update delta_fifo file
update expiration_cache_fakes file
update index_test file
update thread_safe_store file
update events_cache file
update thread_safe_store_test
update expiration_cache_test
small refactor of for loop
unexport the Index type -> index
Kubernetes-commit: c08b9ab3b5c78023e46ce03fde894b24533c68ef
2. Remove staging/src/k8s.io/client-go/tools/cache from .golint_failures;
3. Fix some typo from comments.
Kubernetes-commit: 0e0e1f7daba0a6ae6dd59df0a1bb643c323ad8cb
