"Fade" exact matches that are not the best module

[satazor]

Follow up of npms-io/npms-analyzer#63

Basically, if a exact match appears first but it's not the best module, it should be outlined somehow. We need to come with a good visual solution to make that clear.

[satazor]

An update: now you can specify boost-exact:false to disable this behavior.

[atduarte]

We could add a tag like the "unstable" one, saying "exact match"

[satazor]

I think the flag by itself is not enough. The item should be less "visible" than others.