Fix: Update to version 0.3. This has the following changes:
1. The working directory and ports directory can be specified
in the portsnap.conf configuration file.
2. Parts of the ports tree (down to the level of individual ports)
can be extracted (e.g., "portsnap extract security/freebsd-update").
This also adds an empty file, $PREFIX/portsnap/.package.this.directory,
which (as the name suggests) ensures that $PREFIX/portsnap/ will be
generated when a package is installed using pkg_add.