public static BlockCanary get() {
        if (sInstance == null) {
            synchronized (BlockCanary.class) {
                if (sInstance == null) {
                    sInstance = new BlockCanary();
                }
            }
        }
        return sInstance;
    }
Get {@link BlockCanary} singleton.

@return {@link BlockCanary} instance
blockcanary-android/src/main/java/com/github/moduth/blockcanary/BlockCanary.java