Improve evaluation options

[daniel-lerch]

Vocup currently has just a few options to treat inputs as partly correct instead of incorrect if certain conditions are met. However, it would be more flexible to define a result (correct, partly correct, incorrect) for every case.

[daniel-lerch]

This involves

• A new settings major version aka settings.2.json to change evaluation options to PracticeResult instead of bool.
• Updating the settings UI preferably with a tab in WPF with data binding, but can also stay in Windows Forms.
• Updating the evaluator Vocup.Util.Evaluator.

@jdelange22 please let me know whether you're interested in taking this up or whether I should implement it, as it involves changes to quite a few components.

[jdelange22]

@daniel-lerch I'll take a shot at this, if we first can define the scope of this issue. I'm not really into WPF to be honest. I'll come up with a suggestion first whenever i've got a bit of time to spend.