File args

This pull request partially fixes one of the remaining incompatibilities with remote_syslog 1, by adding the ability to specify log files on the command line.

To make this work I've had to update godaemon to add the option to not chdir (which I've submitted as a [pull request](https://github.com/VividCortex/godaemon/pull/16)). Without that change all filenames had to be absolute, which would be frustrating. I think it's worth waiting to see if that pull request gets accepted before merging this.