s3ws with profiling in /debug/* and interface related bugfix.
s3ws with profiling in /debug/* and interface related bugfix.

- Add import call to fmt and net/http/pprof.
- Convert documentRoot to flag and documentroot.
- Convert sswsIdentifier from var to const and update it to 0.2.
- Check if we've got any ip address back from Addrs() and if not
format an error. Looks like a standard lib bug. Addrs() should set an
error in such case.

stratus/s3ws,stratus/s3ws