Wider character range for more unicode support

[qnub]

If tag contain non latin symbols it'll be removed, but, for, example, in russian language it make files with empty filenames before extension like for блог filename will be .html.eco. So many tags just missed. This solution allow to make files with national characters in names.

[balupton]

I have become too preoccupied by other things to review, merge, and release this PR.

However, you should have received an invite a while ago to join the DocPad Extras Team, which will give you write access to this repository, so you can merge in the PR.

For an orientation, or if you need any assistance following the semi-automatic release process from CONTRIBUTING.md, reach out via https://bevry.me/discord/dev