Add port varient as irssi plugin

[arthur@…]

silc-client can be complied as a plugin for irssi. To enable this I altered the port file to add to the configure options:

--disable-asm \

+ --with-silc-plugin=${prefix}/lib/irssi \ + --without-silc-includes

Ideally this would be a varient and have a dependancy on irssi.

I then needed to bodge the files in /opt/local/lib/irssi/modules to make the module loading work

sudo ln -s libsilc_core.dylib libsilc_core.so sudo ln -s libfe_common_silc.dylib libfe_common_slic.so

I'm sure all of this could be done better, but the functionality is very useful.