Alter bootstrap to handle new FreeBSD pkg changes

FreeBSD's `pkg` system is under development and has changed
it seems since this bootstrap was written.  A new install
of 9.2-Release will not work with the current version.

There are two notable changes

- use the pkg.freebsd repository, which has support for more
  architectures (ll 2337).  the pcbsd site only supports
  amd64, and I at least still have some i386's.

- use the new format for repository conf files (ll 2362-2366)
  The format of conf files has changed and now needs a more
  YAML/JSON like definition.

This is tested on a clean install of 9.2-RELEASE and as the
very first file downloaded it then runs cleanly and
installs salt.

I hope contribution this helps your project