Schedule future check for new articles.
Rename FeedLoader to FeedFetcher.
Remove unnecessary use of named parameters.
Remove unnecessary Stop message for Aggregator.
Add tags field to Feeds.
Clean up FeedStorage message.
Fix unmarshalling of tags from Feed DBObject.
Add import-opml Aggregator API method.
Switch to logback for logging.
Refactor Aggregator to use future instead of FeedFetcher actor.
More refactoring of Aggregator for readability.
Improve error handling off add-feed operation on aggregator.