Bug#672391: Please consider chaging dependency of libsigc++1.2 to 2.0

[Barry deFreese]

I have a patch to pick up libsigc++-2.0.  That is the EASY part.

However, 2.0 is not even close to being binary compatible with libsigc++-1.2.

I will try it for a bit but I am not very familiar with libsigc at all.

Thanks,

Barry deFreese
Debian Games Team