Update to Unicode 15 and bump version to 0.1.22

Author: crlf0710

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 
 name = "unicode-normalization"
-version = "0.1.21"
+version = "0.1.22"
 authors = ["kwantam <kwantam@gmail.com>", "Manish Goregaokar <manishsmail@gmail.com>"]
 
 homepage = "https://github.com/unicode-rs/unicode-normalization"

README.md

@@ -31,7 +31,7 @@ to your `Cargo.toml`:
 
 ```toml
 [dependencies]
-unicode-normalization = "0.1.20"
+unicode-normalization = "0.1.22"
 ```
 
 ## `no_std` + `alloc` support

scripts/unicode.py

@@ -21,7 +21,7 @@
 import collections
 import urllib.request
 
-UNICODE_VERSION = "14.0.0"
+UNICODE_VERSION = "15.0.0"
 UCD_URL = "https://www.unicode.org/Public/%s/ucd/" % UNICODE_VERSION
 
 PREAMBLE = """// Copyright 2012-2018 The Rust Project Developers. See the COPYRIGHT