Improve number input

[supersaiyansubtlety]

adds #321

based on #318

Replaces the JOptionPane dialogs opened by View > Scale > Custom (N%)... and View > Selection Highlight > Blink delay (Nms)... with custom NumberInputDialogs.

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NumberInputDialogs:

• only allow submitting ints/floats within a specified range
• display a red border and error message when the current input is invalid
• play the OS's error chime when invalid input is entered
• have step up/down buttons
• have key binds for cancel, submit, step up/down, and alt step up/down

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Also:

• gives the custom scale dialog a more informative message
• displays any current custom scale in the Custom... menu item
• adds @RangedFloat to Config.main().scaleFactor and reduces the max to 5 (from 10)
• eliminates ScaleChangeListener and ScaleUtil::setScaleFactor; TrackedValue methods make them unnecessary

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Notes:

• uses custom NumberTextFields instead of JFormattedTextFields because the Formats used by JFormattedTextField are too lenient: they seem to ignore all trailing characters after valid input (including . after ints). The NumberTextFields use Integer::parseInt/Float::parseFloat; the only added leniency is trimming leading/trailing white space.
• I considered trying to disallow entering characters that couldn't lead to valid input, but I think it could be counter intuitive (e.g. a user tries to paste a negative number at the end of the current input; it fails because a - cannot be mid-number), and it would require a custom Document which would probably require magical toolkit installation and generally increase complexity.
• I added menu.view.scale.custom.selected translations for French and Japanese based on menu.view.scale.custom assuming the formatting would be the same as in English; I don't speak French or Japanese

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Custom Scale:

initial	max

low	NaN

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Blink Delay:

initial	min

high	NaN