Set backend by RSpec.configuration, not including backend helper
Fix windows spec to use config base backend helper
Fix aix specs to use configure based backend helper
Fix darwin specs to use configuration based backend helper
Fix debian specs to use configuration based backend helper
Fix gentoo specs to use configuration based backend helper
Fix freebsd specs to use configuration based backend helper
Fix redhat specs to use configuration based backend helper
Fix solaris specs to use configuration based backend helper
Fix smartos specs to use configuration based backend helper
Fix solaris10 specs to use configuration based backend helper
Fix solaris11 specs to use configuration based backend helper
Fix helpers specs to use configuration based backend helper
Fix backend specs to use configuration based backend helper
Merge pull request #257 from serverspec/set-backend-by-config-in-specs

[WIP]Set backend by config in specs, not including backend helper