Revision 1728780

Add proxy_module to the list of symbols
detected by Netware export/import awk
script.

We do not export proxy_module by putting it
into modules/proxy/NWGNUproxy explicitely,
because all accompanying proxy modules need
this symbol to access their config. So let
the awk script add proxy_module to the imp
file and then export it from mod_proxy and
import it to all other mod_proxy_xxx modules
via the imp file.