Werkzeug new versions

[EvanBldy]

Hi @noirbizarre,
If we upgrade werkzeug to the last version we can't use flask_fs mostly due to imports.
It's like from werkzeug import secure_filename that have to be from werkzeug.utils import secure_filename.
I fixed everything in my local package.
If I do a PR will you merge and build a new version ?
This repo does not seem to be maintained anymore.