StringMatch should boost matches with uppercase letters in query

[njx]

I was using Quick Open to open "Package.js", and got a lot of higher-ranked hits for "package.json". This is probably not a common case, but it occurred to me that it might be a good idea (and relatively harmless to other use cases) if we give a score boost to an uppercase letter in the query string that matches an uppercase letter in the candidate string (vs. a lowercase letter in the candidate), since if you specifically typed it in uppercase in the query, you probably know it's uppercase in the name you want. (This would have the added bonus of giving an easy way to boost acronym/camel-case searches.)

[njx]

Low pri to @dangoor

[njx]

Reviewed.

[dangoor]

This appears to basically be the same as #3971 and #3694

[njx]

Removing 1.0 milestone - if this does happen to get fixed by the same fix as #2663 (which is still on the 1.0 list) that's cool, but we don't think this one is necessary for 1.0 by itself.