lynx-dev reload_read_cfg & environment variables (say, no_proxy)

[Leonid Pauzner]

dev23 have a new code for undating printers/downloaders lists when
RELOAD THE CHANGES pressed from LYNXCFG:/ page.

Something was done for environments variables also.
I was asking Tom to look into it since I do not know how to clean
environment at run time while we are running the program (not at exit).
Think Tom was overloaded with his other work and lost this minore item.

In particular, I can not change "no_proxy" variable at run-time
from LYNXCFG:/ page (may be useful for some testing purposes).
(And yes, no_proxy not defined as environment on my system without lynx
so configurable from lynx.cfg next session).