Update htmllint.js

* Always sending in -Xss512k, not just for 32-bit systems. Solves an error which happened on my 64-bit Windows 8 running java 1.7.0_67, described here: https://bitbucket.org/sideshowbarker/vnu/issue/4/stackoverflowerror-error-when-running
* The ignore array now supports regular expressions as well as strings.
* Left (“), right (”) and normal (") quotation marks are considered the same when comparing an error message with a string in the ignore array.