enable CommonMark spec 468

A minor adjustment to the href-matching regexp permits CommonMark spec
468 to pass. All other passing specs are unaffected.

The regexp was incorrectly excluding parentheses as valid characters in
a URL.

Author: Trott

lib/marked.js

@@ -544,7 +544,7 @@ inline.tag = edit(inline.tag)
   .getRegex();
 
 inline._label = /(?:\[[^\[\]]*\]|\\[\[\]]?|`[^`]*`|[^\[\]\\])*?/;
-inline._href = /\s*(<(?:\\[<>]?|[^\s<>\\])*>|(?:\\[()]?|\([^\s\x00-\x1f()\\]*\)|[^\s\x00-\x1f()\\])*?)/;
+inline._href = /\s*(<(?:\\[<>]?|[^\s<>\\])*>|(?:\\[()]?|\([^\s\x00-\x1f\\]*\)|[^\s\x00-\x1f()\\])*?)/;
 inline._title = /"(?:\\"?|[^"\\])*"|'(?:\\'?|[^'\\])*'|\((?:\\\)?|[^)\\])*\)/;
 
 inline.link = edit(inline.link)

test/specs/commonmark/commonmark-spec.js

@@ -349,7 +349,7 @@ describe('CommonMark 0.28 Links', function() {
   var section = 'Links';
 
   // var shouldPassButFails = [];
-  var shouldPassButFails = [468, 474, 478, 483, 489, 490, 491, 492, 495, 496, 497, 499, 503, 504, 505, 507, 508, 509, 523, 535];
+  var shouldPassButFails = [474, 478, 483, 489, 490, 491, 492, 495, 496, 497, 499, 503, 504, 505, 507, 508, 509, 523, 535];
 
   var willNotBeAttemptedByCoreTeam = [];