Please review and merge it,
Thank advance

added a missing argument

Fixes #2392: Added `addCssStyle()`, `removeCssStyle()`, `cssStyleFromArray()` and `cssStyleToArray()` to `Html`

- supports GFM now
- allows defining different flavors

fixes #47

Why use a strong random number generator in one place, but not another? I know salts have no cryptographic security requirement, but collisions are less likely if you use one.