absent a.out

The process finding command didn't work for me so I ended up with the old process blocking the port for the new one. This fix makes it work but it finds a bit too many processes most of the time (the shell one that starts the go one - for example) and fails to kill them when they get killed implicitly. I don't know enough about things like this to make sure it works flawlessly. 

I'm on OS X 10.8.3.