Code review comment for lp:~widelands-dev/widelands/gcc7

The gcc-7 package should be available now https://launchpad.net/~ubuntu-toolchain-r/+archive/ubuntu/test?field.series_filter=trusty. I've merged latest trunk a couple of times, but it didn't seem like bunnybot picked up the changes.

I suspect this might be related to the MP status, so I've taken the liberty of moving it back to needs review.