remove ohai dev gems

the sigar gem makes solaris and freebsd very unhappy
add comment about possible cargo cult
we use static libgcc now
fixup ohai to remove dev gems

removes the bundle exec from 'rake gem', also should handle the
appbuilder case for chefdk correctly.
Merge pull request #237 from opscode/lcg/remove-ohai-dev-gems

remove ohai dev gems
use :aix => :use_gcc for libtool
Add `cpanminus` software definition

This fast, modern CPAN client allows a greater level of configuration
than the default `cpan`. The project describes itself as follows:

“Cpanminus is a script to get, unpack, build and install modules
from CPAN and does nothing else. It's dependency free (can bootstrap
itself), requires zero configuration, and stands alone. When running, it
requires only 10MB of RAM.”

More info here:
https://github.com/miyagawa/cpanminus#questions

This is also the CPAN client Travis CI uses:
http://docs.travis-ci.com/user/languages/perl/#Dependency-Management
Use `cpanminus` to install Perl module deps

We’ll also ensure we don’t run tests when installing CPAN modules. Go
read this if you need a reason why this is insane:
http://www.openswartz.com/2012/01/31/stop-running-tests-on-install/

We’ve hit issues where a modules test’s fail (and thus the module is NOT
installed) and the default `cpan` client continues along and exits with a
zero status!
Add a real version/md5 to `perl_pg_driver`
fix hash syntax
Only apply dl.rb patch on Ruby 2.X.
Merge pull request #241 from opscode/schisamo/no-perl-tests

Perl Improvements
Merge pull request #243 from opscode/lcg/aix-gcc-compile

additional fixes for new omnibus-ruby
add bundler dep to ffi-yajl

need it for the bundle install of course
Merge pull request #244 from opscode/lcg/add-bundler-dep

add bundler dep to ffi-yajl
adding fiddle back because ffi-yajl needs it
add libffi as a dep to fix fiddle
remove old solaris compiler junk
use new standard omnibus-ruby helper functions

call out the non-standard flags in ruby compiles explicitly.
pass in env correctly