Memory leak fixed.

[Michael Polak]

I have just fixed memory leak in release 1.68  (eg. crashing when
you reload chat.arachne.cz several times, etc.)

Additionaly, I saved 2 KB of DOS memory and removed limit on number of
form widgets in HTML page (number of TEXTAREA fields and INPUT fields in
FORMs) is now limited only by xSwap size, not DOS memory size. This is
big improvement, and it's a shame that it took me 4 years to find out
how simply it can be done...