Update hypertext page to new <tex> tag semantics.

Inline mathematics is the default now.
For displayed mathematics use <tex p>.

<tex>..</tex>
    inline mathematics (compact notation, smaller font)
    Formerly: <tex inline>

<tex p>..</tex>
    displayed mathematics (own paragraph)
    Formerly: <tex>

So, <tex inline> is no longer functional.

=> If you use the <tex> tag on your pages, you must adapt them.