Bring in changes from the process isolate.

Adapt current working directory path from the process isolate, as well
as use the quick exit path on post-fork failures.
Enable URLFetch service packaging.

The one and only nuclear-powered coder Ruslan Nigmatullin finally
managed to packetize his Swarm library, so we can enable building of
the URLFetch packages.
Copyright header bump.

It's year 2013 already, time to bump our useless copyright headers. Also
fixed a typo in Ruslan's last name.