Make sourcecode compatible with ansi2knr again

This allows to compile ngIRCd using a pre-ANSI K&R C compiler again:
all source files are automatically converted by the included ansi2knr
program (of GNU automake/autoconf) before compiling them with the
K&R C compiler, but a few coding standards must be met.

Tested on Apple A/UX 3.x.
Regression testing on Linux and Mac OS X.