Fallback to NFKC Normalization

[JamoCA]

I was attempting to normalize some domain names that were using high ascii characters. I was able to properlly convert them to ASCII using java.net.IDN's toASCII(), but not Junidecode. I kept receiving "java.lang.NullPointerException" errors.

Here are some sample strings that caused errors (I hope this works):

• ℰ𝒳𝒜ℳ𝓟ℒℰ
• 🄴🅇🄰🄼🄿🄻🄴
• ⓔⓧⓐⓜⓟⓛⓔ

I was able to use Junidecode to convert to ASCII7, but the steps required testing if NullPointerException error occurs and then normalize using NFKC and reattempt Junidecode.

Here's the ColdFusion/Java function that I used to normalizeUTF. (Should this be performed on all strings before attempting to convert?)

/* NFKC: UTF Compatibility Decomposition, followed by Canonical Composition */
function normalizeUTF(inputString){
    var normalizer = createObject( "java", "java.text.Normalizer" );
    var normalizerForm = createObject( "java", "java.text.Normalizer$Form" );
    return normalizer.normalize( javaCast( "string", arguments.inputString ), normalizerForm.NFKC );
}

I've also identified that if this approach is used, you won't have to add extra character matching to support "Enclosed Alphanumerics".

[JamoCA]

JUnidecode 0.5.2 doesn't throw a NullPointerException error anymore. (I previously explicitly used try/catch with the function.)

On this "Unicode Text Converter" webpage (https://qaz.wtf/u/convert.cgi), a plain text string (letters, sometimes numbers, sometimes punctuation) is converted to obscure characters from Unicode. I used this for testing in an attempt to convert the strings back to ASCII7 using JUnidecode. Strings that contain Low Surrogates, Enclosed Alphanumerics or Emoticons code are required to be sanitized using the previously mentioned method prior to using JUnidecode or nonsense is returned.

Here are the UTF-8 strings that I've been using for unit tests:
https://gist.github.com/JamoCA/8fe790651d7c4fe869e755cdeebfd051

Here are the string conversions that are performed on the converter webpage:

• Enclosed Alphanumeric
• Circled
• Circled (neg)
• Math bold
• Math bold Fraktur
• Math bold italic
• Math bold script
• Math double-struck
• Math monospace
• Math sans
• Math sans bold
• Math sans bold italic
• Math sans italic
• Parenthesized
• Regional Indicator
• Squared
• Squared (neg)
• CJK+Thai pseudoalphabet
• Curvy 1 pseudoalphabet
• Curvy 2 pseudoalphabet
• Curvy 3 pseudoalphabet
• Faux Cyrillic pseudoalphabet
• Faux Ethiopic pseudoalphabet
• Math Fraktur pseudoalphabet
• Small Caps pseudoalphabet
• Subscript pseudoalphabet
• Superscript pseudoalphabet
• Inverted pseudoalphabet
• Inverted pseudoalphabet (backwards)
• Reversed pseudoalphabet
• Reversed pseudoalphabet (backwards)