Fix HTML comment parsing with - before closing --> (#286)

Fixes #285.

Author: robinst

lib/common.js

@@ -24,7 +24,7 @@ var ATTRIBUTEVALUESPEC = "(?:" + "\\s*=" + "\\s*" + ATTRIBUTEVALUE + ")";
 var ATTRIBUTE = "(?:" + "\\s+" + ATTRIBUTENAME + ATTRIBUTEVALUESPEC + "?)";
 var OPENTAG = "<" + TAGNAME + ATTRIBUTE + "*" + "\\s*/?>";
 var CLOSETAG = "</" + TAGNAME + "\\s*[>]";
-var HTMLCOMMENT = "<!-->|<!--->|<!--(?:[^-]|-[^-]|--[^>])*-->"
+var HTMLCOMMENT = "<!-->|<!--->|<!--[\\s\\S]*?-->"
 var PROCESSINGINSTRUCTION = "[<][?][\\s\\S]*?[?][>]";
 var DECLARATION = "<![A-Za-z]+" + "[^>]*>";
 var CDATA = "<!\\[CDATA\\[[\\s\\S]*?\\]\\]>";

test/regression.txt

@@ -502,3 +502,19 @@ x<!>
 <p>x<!x></p>
 <p>x&lt;!&gt;</p>
 ````````````````````````````````
+
+#285
+```````````````````````````````` example
+foo <!-- test --->
+
+foo <!-- test ---->
+
+foo <!----->
+
+foo <!-- test --> more -->
+.
+<p>foo <!-- test ---></p>
+<p>foo <!-- test ----></p>
+<p>foo <!-----></p>
+<p>foo <!-- test --> more --&gt;</p>
+````````````````````````````````