Fix kubrowser slowness

[brianpipa]

Once we get a significant amount of books, the browsing of the larger genres is slow. Do something to fix this.

I wonder if we could cache all the kubrowser info right after we do the cleanups. Also, may need to hide any that have less than, maybe 5?

[brianpipa]

ok, I think i have fixed this - for now. I chopped off the KU results at 200 for now and i optimized the code a bit and it seems to be much faster now.