cwrappers test diff

[Jonathan Perkin]

A number of people have asked to try out the cwrappers work, so I've
generated a diff of where I've currently got to:

http://us-east.manta.joyent.com/pkgsrc/public/patches/cwrappers-test.diff

All you need to do is bootstrap and then start using those tools. If
you want to use native, then build and install pkgtools/cwrappers,
then add USE_CWRAPPERS=yes to your mk.conf

There are still a number of issues, so expect to see some failures,
issues I'm currently tracking are:

- Fortran is currently broken.

- cwrappers do not support fnmatch expressions, and there are various
uses in pkgsrc, mostly of the -O[0-9]* variety.

- The cwrappers environment is stricter, passing through fewer paths,
notably those under /usr/include/* and /usr/lib/*. I believe this
to be a good thing, though it will require fixups.

You can compare two reasonably identical builds to see the difference
(bulktest is the one with cwrappers enabled):

http://us-east.manta.joyent.com/pkgsrc/public/reports/upstream-trunk32/20140909.2232/meta/report.html
http://us-east.manta.joyent.com/pkgsrc/public/reports/upstream-bulktest/20140912.0949/meta/report.html

Enjoy,