public static FeedKeyInterner createInterner() {
        return new FeedKeyInterner();
    }
Creates an {@link FeedKeyInterner} to intern FeedKey instances to reduce the
total number of unique {@link FeedKey} instances in memory.
<p>Not thread safe. Only for local use.</p>
stroom-proxy/stroom-proxy-repo/src/main/java/stroom/proxy/repo/FeedKey.java