Smarter Mana Cost sorting

[ZeldaZach]

Fixes #3006

If you input a partial mana cost, all cards that meet that mana cost requirement will appear.

Sort the mana costs input as well so UU1 == U1U == 1UU == uu1 == ...

Examples:

[tooomm]

• Lower case input now works, too!
• Order isn't strict anymore (gb finds "Abrupt Decay" as well)

The Mana Cost filter is finally intuitive and usable! Well done, Zach. 👍

Can you please check the code itself, @Daenyth?

[ctrlaltca]

This is definitely a nice addition; it will just make the filter a bit slower because of the repeated toUpper() calls.

[ZeldaZach]

@ctrlaltca Do you think using the Qt::CaseInsensitive check would be more efficient?

[ctrlaltca]

Do you think using the Qt::CaseInsensitive check would be more efficient?

Maybe a little bit, since the Qt implementation of indexOf() is comparing characters one by one, but since mana cost strings are typically really short, it won't be noticeable.
Of course i'd love to be proven wrong with some actual performance benchmark.