Forbid <, >, and ^ in hosts

Tests: web-platform-tests/wpt#23572.

Closes #458.

url.bs

@@ -339,8 +339,8 @@ processing.
 <h3 id=host-miscellaneous>Host miscellaneous</h3>
 
 <p>A <dfn export>forbidden host code point</dfn> is U+0000 NULL, U+0009 TAB, U+000A LF, U+000D CR,
-U+0020 SPACE, U+0023 (#), U+0025 (%), U+002F (/), U+003A (:), U+003F (?), U+0040 (@), U+005B ([),
-U+005C (\), or U+005D (]).
+U+0020 SPACE, U+0023 (#), U+0025 (%), U+002F (/), U+003A (:), U+003C (&lt;), U+003E (>), U+003F (?),
+U+0040 (@), U+005B ([), U+005C (\), U+005D (]), or U+005E (^).
 
 <p>A <a for=/>host</a>'s <dfn for=host export>public suffix</dfn> is the portion of a
 <a for=/>host</a> which is included on the <cite>Public Suffix List</cite>. To obtain
@@ -3461,7 +3461,8 @@ Tristan Seligmann,
 Valentin Gosu,
 Vyacheslav Matva,
 Wei Wang,
-山岸和利 (Yamagishi Kazutoshi), and
+山岸和利 (Yamagishi Kazutoshi),
+Yongsheng Zhang, and
 成瀬ゆい (Yui Naruse)
 for being awesome!