#48 [patch] better support for awk scripts

[Thomas Braun]

Hello,

I modfied awk.c to get support for the following features:
- BEGIN,END,{ special patterns
- FNR == $number { special pattern
- NR == $number { special pattern

The implementation is a bit dump, but it works reliable.

Thanks for the cool program :)

[Thomas Braun]

patch against exuberant tags 5.7