Levelling options

Starsaber

When raising the level of your characters, you currently have two options:

* Hold down to put Iso into a character until they level up
* Two taps/clicks to raise the character to their current level max.

I would like to see a third option, which would allow you to spend all your current Iso on the character in two taps/clicks. It's kind of annoying when you have enough Iso for multiple levels, but since it wouldn't take you to the character's current max level, you have to raise their level one at a time.