Improve cookbook search

:fork_and_knife: To provide better search results based on name this weights cookbook name over cookbook description. Since there are also a lot of cookbooks with similar names (redis, redisio, redis-test etc.) this also takes into account follower count to surface the more common cookbooks to the top of results. Presumably we'll need to continue to tweak search as we discover use cases from the user base but this is a step in the right direction.
What's better for the user? In this case, making search more lenient seems to be better for the user. I would expect to find "jam2" in the search results for "jam" (see also: searching for "apache" and seeing "apache2" listed).