Throw ContainerNotFoundException from removeBlob

This makes removeBlob consistent with all other user-facing methods.

blobstore/src/main/java/org/jclouds/blobstore/LocalAsyncBlobStore.java

@@ -229,6 +229,9 @@ public class LocalAsyncBlobStore extends BaseAsyncBlobStore {
     */
    @Override
    public ListenableFuture<Void> removeBlob(final String container, final String key) {
+      if (!storageStrategy.containerExists(container)) {
+         return Futures.immediateFailedFuture(cnfe(container));
+      }
       storageStrategy.removeBlob(container, key);
       return immediateFuture(null);
    }