Two minor changes (both on line 307) to conform to the Unicode Standard.

Unicode code points currently display with:

1. Lowercase letters, a - f, when present
2. A leading 0 for 5-digit code point values (i.e. 10000 - 9ffff)

However, the Unicode Standard specifies that when using the "U+" notation, you should use:

1. Uppercase letters
2. Leading zeros only when the code point would have fewer than four digits (i.e. 0000 - 0FFF)

For reference, the Unicode Standard (two versions to show consistency over time)

* [(Version 12.1, 2019) Appendix A: Notational Conventions ⇒ Code Points](http://www.unicode.org/versions/Unicode12.0.0/appA.pdf)
* [(Version 4.0.0, 2003) Preface: Notational Conventions ⇒ Code Points](http://www.unicode.org/versions/Unicode4.0.0/Preface.pdf)

states:

> In running text, an individual Unicode code point is expressed as U+n, where n is four to six hexadecimal digits, using the digits 0–9 and uppercase letters A–F (for 10 through 15, respectively). Leading zeros are omitted, unless the code point would have fewer than four
hexadecimal digits—for example, U+0001, U+0012, U+0123, U+1234, U+12345, U+102345.