Add XML and mbstring extensions to the list of required in `readme.html`. `readme.html` adjusted according to `readme.md`.
Add XML and mbstring extensions to the list of required in `readme.html`.
`readme.html` adjusted according to `readme.md`.

nazar-pc/CleverStyle-CMS,nazar-pc/CleverStyle-CMS,nazar-pc/CleverStyle-Framework,nazar-pc/CleverStyle-Framework,nazar-pc/CleverStyle-CMS,nazar-pc/CleverStyle-Framework,nazar-pc/CleverStyle-CMS,nazar-pc/CleverStyle-Framework